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Last update: 2016-10-06 (Correction of typographical error)

Largely summarized from:
Alexander Gode and Hugh E. Blair
Interlingua: a grammar of the international language
New York: Frederick Ungar Publishing Co., 1955 (2nd edition)
ISBN 0-8044-0186-1
(with some supplemental material)

(This summary is not a complete statement
of Interlingua grammar and usage.)


Spelling and Pronunciation

Interlingua is written with the conventional twenty-six letters of the Latin alphabet without diacritical or accent marks. Proper names and unassimiliated foreign words may have letters with diacritical or accent marks and retain their foreign pronunciation.

In general, pronunciation is "continental," similar to that in western Europe. However, sounds are somewhat fluid within types and may be influenced in part by neighboring sounds and by the native habits of speakers. The emphasis in speech is for comprehension, not meticulous exactness of enunciation. Vowel sounds (and letters) are generally pure and coincide mostly with Romance pronunciation (although written u is not pronounced as the sound represented by the single letter in French lune.) English speakers, in particular, must take care not to obscure the pronunciation of unstressed vowels.

The following letters agree with the normal English pronunciation: b, d, f, k, l, m, n, p, ph, qu, v, w, z.

c before e, i, y is pronounced like ts; otherwise (as also ch) like k.
g like g in good (like z in azure in the suffix -age).
h as in English (or optionally silent for some speakers), except silent after r and t.
j like z in azure. (Some speakers pronounce as g in gem or y in yes.)
r will vary somewhat according to the native habits of speakers, but speakers of some dialects of English must take care not to elide it after vowels.
s generally unvoiced, but voiced or unvoiced between vowels (ss unvoiced between vowels).
t as in English; ti before vowels varies somewhat among speakers but often as tsy unless stressed or preceded by s.
x generally as in English.
y unstressed before vowels as y in yes; otherwise as i.

Vowels in diphthongs retain their independent sound values, except that unstressed i and u become semiconsonants before following vowels. Stressed e and i are separated by a syllable break from a following a, e, o. Double consonants merge in pronunciation.

A main stress accent falls normally on the vowel before the last consonant (except that the plural ending does not change the stress from the singular form). Adjectives and nouns ending in -le, -ne, and -re preceded by a vowel have the stress on the antepenultimate syllable. The stress falls on the syllable preceding the suffix in words formed with the suffixes -ic, -ica, -ico, -ida, -ide, -ido, -ima, -ime, -imo, -ula, -ule, -ulo, -uple, and -ulo. Variations from stress rules are marked in dictionaries. (See also the section on verbs, below.)

Stress regularity should not be exaggerated. Understandability is the principal concern. Stress is not random, but the Interlingua word is the same whether it is pronounced, for example, kilOmetro or kilomEtro, according to speakers' native habits.

Within a sentence, proper names are capitalized but not derivatives from them. Punctuation marks and their values are generally those of English but need not obey absolute rules as long as they follow the rhythms of the spoken sentence and the sense is clear.

Collateral Orthography

There is an allowed collateral orthography, which is employed by some users (although only occasionally used):

  1. Double letters representing a single consonant sound are replaced by the single consonant letter, except for ss, which is kept doubled to preserve the sound. (cc before e, i, y does not represent a single consonant sound.)
  2. Vowel y > i
  3. ph > f
  4. ch representing the sound of k is retained only before e and i; elsewhere it is replaced by c.
  5. For silent h, rh > r and th > t.
  6. J replaces g and gi to represent the sound of z in azure.
  7. Suffix -age (and terminal sound group -age when it is not a suffix) is replaced by -aje. Suffix -isar is replaced by -izar (and z appears in its derivatives).
  8. Final e is dropped after t preceded by a vowel except in words which have the stress on the antepenultimate syllable. Likewise for final e after n, l, and r when these are shortened collateral spellings under item 1. above. (Present tense and imperative verb forms are not affected by this rule.)


Le is the definite article, the, and is invariable. It does not change (when used as an article; see below) for number or gender and is generally used as in English, with some variations, such as that it is not omitted with abstract nouns representing the entire class, species, etc. It need not be omitted with titles preceding proper names (except in direct address).

Un is the indirect article, a(n), and also is invariable. It is identical with the numeral un, 'one'. (When used as a numeral, un sometimes appears in the plural form unes in certain vocabulary expressions such as le unes le alteres, 'one another, each other, etc.'.)

A preceding preposition a or de fuses with an immediately following definite article into the forms al or del. Both articles have the possibility of pronominal use, and in such instances can be pluralized as les and unes (the latter often being rendered as 'some'). In pronominal use, the articles can make a distinction between male and female (not grammatical gender) as le/la and uno/una, all of which have plural forms. The definite article has a neuter pronominal form lo which occurs especially in the expression lo que, 'that which, what'. (It has a rarely used plural los in this construction.)


Nouns are recognized by the function they perform in a sentence rather than by a specific set of endings. There is no grammatical gender, although some nouns can indicate a difference of natural sex. (If a noun ending in o specifically indicates a male being, the ending a can indicate the female, and vice versa.) There are no distinct case forms.

The plural is formed by the addition of s after a vowel and es after a consonant. (Final c changes to ch before the plural marker es in order to preserve the pronunciation.) Unassimilated foreign words may retain their foreign plurals. Formation of the plural does not affect accentuation.

Nouns function generally as in English. Note, however, that the widespread English trait of nouns being used extensively as adjectives or attributives before other nouns does not occur in Interlingua. (Nevertheless, proper nouns used as adjectives remain unmodified and are preceded by the nouns they qualify, e.g., 'Roentgen rays', radios Röntgen; 'Geiger counter(s), contator(es) Geiger).


Although adjectives most commonly end in e, c, l, n, or r, these final letters are not conclusively indicative that a word is an adjective, which can only be determined by the function it performs in a sentence or, at times, by a suffix which happens to occur with no other part of speech.

Adjectives do not have inflection, nor do they agree with the nouns they modify. Adjectives may either precede or follow a noun. The latter position is more frequent. "Adjectives preceding a noun tend to suggest that what they express is an essential feature of the noun concept and not merely a feature distinguishing the present representative of the noun concept from others." [p. 13, §33] However, brief adjectives such as bon, parve, alte, etc., may precede their nouns as a matter of rhythm or personal preference.

The adverbs plus (for the comparative) and minus, together with the article le (for the superlative) form degrees of comparison. (See below for a few irregular alternative comparisons.) A so-called absolute superlative (very, most, etc.) is expressible with the suffix -issime.

When the sense allows, adjectives can be used as nouns or pronouns, in which case they can be pluralized and/or take the article.

Alternative Comparisons

parve plus parve, minor le plus parve, le minor, minime
small smaller/lesser smallest/least
magne plus magne, major le plus magne, le major, maxime
great greater greatest
bon (adj) plus bon, melior le plus bon, le melior, optime
ben (adv) plus ben, melio le plus ben, le melio, optimo
good/well better best
mal (adj) plus mal, pejor le plus mal, le pejor, pessime
mal (adv) plus mal, pejo le plus mal, le pejo, pessimo
bad(ly) worse worst


Adverbs may be either primary or derived; there are also adverbial phrases. Primary adverbs are dictionary items and require no grammatical remarks. Adverbs derived from adjectives are formed with the suffix -mente (-amente after a final c) appended to the full form of the adjectives. The functions of adverbs are largely those of English adverbs.

A few adverbs which seem to be derived irregularly from adjectives (such as bon/ben) can be treated as primary adverbs, in that they do not serve for additional adverbial derivations. However, regular derivation (such as bonmente = ben) is still possible.

Regular comparison of adverbs is the same as that of adjectives. Adjectives in -issime can form corresponding adverbs in -issimo.

Adverbs (except those indicating a certain determined time) usually precede the words they modify. (Longer adverbs may follow, for emphasis or style.) When an adverb or adverbial phrase modifies a clause or sentence as a whole, it appears in initial or final position or is set off by commas. When an adverb (especially non) and a non-subject pronoun both precede a verb, the pronoun is closer to the verb. The adverb non precedes the verb it modifies.

An and esque are interrogative particles which have no immediate counterparts in English and which convert a simple declarative sentence into a question. They should not both be used in a single text.


Personal pronoun table:

                   OBJ              POSS    POSS
         SUBJ      PREP  OBJ  REFL  ADJ     PRON

1p sg    io    mi      mie
2p sg    tu        ......te.....    tu      tue
3p sg m  ille..........  le   se    su      sue
3p sg f  illa..........  la   se    su      sue
3p sg n  illo, il......  lo   se    su      sue

1p pl    nos....................    nostre......
2p pl    vos....................    vostre......
3p pl m  illes.........  les  se    lor     lore
3p pl f  illas.........  las  se    lor     lore
3p pl n  illos.........  los  se    lor     lore

         on        uno..........................

[NOTE: usage of the second person singular pronoun tu and its forms varies. Some users employ it merely as a singular form without connotation of familiarity, and some users employ it particularly as a familiar form, extending vos and its forms to both singular and plural.]

cuje : "whose"
qui : "who, whom" only for persons and only as a subject or after prepositions
que : (primarily) relative pronoun
qual : relative adjective (can be pronominalized with le and then pluralized: le qual and le quales)
(Relative pronouns are not elided in Interlingua as they sometimes are in English.)
il : an unstressed third person singular neuter form for use as a grammatical subject (sometimes elided)
ella : a collateral (now rarely used) form for illa
In the plural, illes does not necessarily indicate a plurality of masculine beings.
Possessive pronouns are often used with le : Illo es le mie. = It is mine.

Reflexive constructions are primarily of the type in which the object of the verb happens to be logically identical with the subject. ... Reflexive constructions are also used to express passive ideas when there is no agent involved.
Second-case personal and reflexive pronouns (except in prepositional constructions) precede the simple tense forms of the verb but follow the participles, imperative forms, and the infinitive.
[Interlingua Grammar p. 25, §§67-69]

"In a combination of two pronouns, one personal and the other reflexive, the latter precedes."

Demonstratives are adjectives which can be used as pronouns. Iste, this, is the demonstrative of proximity. Ille, that, is the demonstrative of remoteness.



model: -ar -er -ir
INFINITIVE crear vider audir
PRESENT PARTICIPLE creante vidente audiente
PAST PARTICIPLE create vidite audite
IMPERATIVE crea! vide! audi!
PRESENT crea vide audi
PAST creava videva audiva
PRESENT PERFECT ha create ha vidite ha audite
PAST PERFECT habeva create habeva vidite habeva audite
FUTURE creara videra audira
FUTURE PERFECT habera create habera vidite habera audite
CONDITIONAL crearea viderea audirea
CONDITIONAL PERFECT haberea create haberea vidite haberea audite

In the future tense, the a ending receives the word stress; in the conditional, the e of the ending receives the stress. Some users employ the auxiliary verb va plus the infinitive to express the future, as in English.

Passives are formed from the corresponding tenses of esser plus past participle. Reflexive constructions can be used to express passive ideas when there is no agent involved.

There is no verbal auxiliary corresponding to English to do in interrogative, negative, and emphatic constructions, and there are no crystallized progressive forms.

The infinitive can be used to express general orders, prohibitions, etc.

The following alternative forms are available:

es = esse (singular/plural)
son = esse (plural)
era = esseva
sia = esse (optional irregular subjunctive or imperative)
ha = habe
va = vade

Apart from (the only occasionally used irregular) sia, there is no distinct subjunctive. Subjunctive or third-person imperative is often expressed by the indicative following que.

The infinitive [Inf.] serves as a verbal noun in place of the English gerund.

Prepositions before Infinitives

a + Inf. Inf. seems to represent a goal or aim either after an adjective or a verbal construction; Inf., usually with an expressed or understood esser, is actually passive in meaning; after nouns or adjectives relating to quantity; with transitive verbs and their direct objects
pro + Inf. in order (to); purpose
<nothing> + Inf. when Inf. serves as a noun; Inf. depending on a transitive verb; after il + verb + noun/adjective where the Inf. can replace il with same meaning
<nothing> + Inf. after constructions with voler, poter, deber, soler, lassar, vader, facer, as well as vider, audir, and other verbs of sense perception when they have an object which is at the same time the subject of the following infinitive; after que and qual
de + Inf. neutral preposition; what the subject can do itself (adjectival construction); not as direct object of verb
Subj. (accus.) + Inf. <make subordinate clause with que>
'of' de + Inf.

If an infinitive can be construed as a noun or taking the place of a noun, no preposition need be used. For example, in the expression "It is difficult to walk in the sand," the infinitive is equivalent to the logical subject and hence the equivalent of a noun: "To walk in the sand is difficult," so there is no preceding preposition: [Il] es difficile vader in le arena or Vader in le arena es difficile. If a transitive verb is followed by a dependent infinitive, as in "I plan to go to the countryside" (Io plana vader al campania), the idea can also be expressed more or less smoothly by a noun ("I plan a trip to the countryside"), so again, no preposition is used. Thus, a preposition does not introduce a dependent infinitive after a transitive verb.
(Interlingua Grammar §87, p. 31)

[NOTE: Because the source languages for Interlingua are not entirely consistent among themselves on the use of prepositions before infinitives, use or non-use of the prepositions de and a before infinitives varies somewhat in practice among speakers and writers, as long as the intended sense is clear.]

Double-Stem Verbs

Forms derived from certain verbs come from a second or double stem, often based on the Latin supine stem.

In Interlingua the irregular second stem of verbs has nothing to do with matters of conjugation. It is a stem which occurs in certain derived nouns and adjectives and prevents these from assuming unnaturally distorted forms .... Furthermore, the "regular" type ... need not be considered "wrong" but may be used whenever it seems stylistically possible or preferable.
    In active word bulding it will be found that the irregular second stem occasions few difficulties but often simplifies the process of derivation.
[Interlingua Grammar page 85, Appendix 1]


Sunday dominica January januario
Monday lunedi February februario
Tuesday martedi March martio
Wednesday mercuridi April april
Thursday jovedi May maio
Friday venerdi June junio
Saturday sabbato July julio
    August augusto
    September septembre
    October octobre
    November novembre
    December decembre

[NOTE: For avoidance of any contemporary religious connotations for name days, one occasionally encounters the non-standard, unofficial forms soldi and saturdi for Sunday and Saturday, respectively.]


0 zero   [ordinals:]
1 un 10 dece 1me prime
2 duo 20 vinti/viginti 2nde secunde
3 tres 30 trenta 3tie tertie
4 quatro 40 quaranta 4te quarte
5 cinque 50 cinquanta 5te quinte
6 sex 60 sexanta 6te sexte
7 septe 70 septanta 7me septime
8 octo 80 octanta 8ve octave
9 nove 90 novanta 9ne none
    10me decime
  100 cento 100me
  1.000 mille last: ultime

For other numbers, <ordinal> = <cardinal> + -esime
adverbial numerals: ordinal -e > -o or use -mente

half = medie/medietate
dozen = dozena
Other collective numerals are formed on the pattern of the suffix -ena(s) attached to the simple cardinal numbers.

cento 100
mille 1.000
million 1.000.000

Comma for decimal point.
-illion/-illiardo de <cosas>

simple simple/simplice
double duple/duplice
triple triple/triplice
quadruple quadruple
quintuple quintuple
sixfold sextuple
sevenfold septuple
eightfold octuple
ninefold nonuple
tenfold decuple
100fold centuple

Grammatical Words

a to; at; (bottilia a lacte = bottle for milk)
ab (prep) since, from
alias otherwise, in another manner; alias; at another time
alibi elsewhere
ali(c)- any-, some-
alicubi somewhere; anywhere
alicun [sometimes alcun] some, any; a few; alicun cosa: something, anything
alicuno [sometimes alcuno] someone, somebody; anyone, anybody
aliquando sometime; at any time
aliquanto somewhat, to some degree
alique (pron) something, anything; (adv) somewhat
alora then; in that case, consequently
alto top; in alto: up; upwards; upstairs; on top
ambe (adj) both; ambes: (pron) both
an (interr part) --; an il habe le libro?: does he have the book?; (conj) whether
ancora (adv) still, yet; (interj) encore
anque also, too; anque io: me too; non solo ... ma anque: not only ... but also
ante (prep) before, in front of; earlier than; above; (adv) before, ahead; earlier; forward; ante que: before
ante-heri day before yesterday
a pena hardly, scarcely
apud near, with, at, by
assatis (adv) enough; rather, fairly, quite
assi thus, so; assi ... como: as ... as
avante before, in front, ahead; forward
basso bottom; a basso: down, downward; in basso: down, below, downward; downstairs
bastante (adj) enough, sufficient; (adv) enough, sufficiently
ben que although
bis twice; encore
cata (adj) each; cata uno: each (one)
causa cause; a causa de: because of
certo certainly
circa around, about; approximately
como how; as, like; como si: as though, as if
comocunque however, in whatever way
con with, together with; by means of
concernente concerning
contra (prep) opposite, facing; against; (adv) opposite, facing; on the contrary
cuje whose
-cunque -ever
de from, since; of, belonging to; made of; with, by means of; de (+inf): to; (bottilia de lacte = bottle [quantity] of milk)
deman tomorrow; deman matino: tomorrow morning; deman vespere: tomorrow night
depost (adv) afterwards, later; (prep) after, since; depost que: since, from the time that
desde (prep) since, from
dum while, as long as; until; provided that, if only
dunque therefore
durante during; durante que: while, whilst
e and; e ... e: both ... and
ecce lo!, see!, behold!; here is, here are
ergo therefore, accordingly, consequently, then, ergo
esque (interr part) esque ille ha le libro?: does he have the book?
et cetera, etc. and so forth, and so on, et cetera, etc.
etiam also, likewise, too; even, even yet, yet; non solmente ... sed etiam: not only ... but also
ex out of, from
excepte except, excepting
extra (adv) without, on the outside; besides, in addition, extra; (prep) outside of, without, beyond; except, excepting; besides, in addition to
foras (adv) out of doors, outside, out; from without; (prep) beyond, except; foras de: outside of, without; foras de se: beside oneself
forsan perhaps, maybe
gratis gratis, free of charge
haber to have; il ha: there is, there are
heri yesterday
hic here; de hic a (un hora): (an hour) from now; usque (a) hic: up to here, thus far; up to now, hitherto; hic juncte: herewith
hodie today
ibi there
ibidem in the same place; ibidem; ibid.; ib.
idem the same (thing); idem; id.
igitur (adv/conj) then, therefore, thereupon
il (impers pron) it; il ha/habeva: there is(are)/was(were)
illa she, her
illac there
ille he, it; him; that, the former
illes they; them
illo it
in in, into
infra (adv) below, underneath, beneath; (prep) below, under, beneath
insimul together
inter between, among
interim meanwhile, in the meantime
intertanto meanwhile, in the meantime
intra (adv/prep) within
intro inwardly, internally, on the inside, in
io I
ipse myself, yourself, himself, etc.; hodie ipse: this very day
iste this, the latter
ita thus, so; just so, yes; and so, consequently; accordingly
jam already, at once, right away; just now, a moment ago; indeed, surely; non ... jam: no longer
jammais ever, at any time; non ... jammais: never; jammais!: never!
justo just, exactly; justo nunc, justo ora: just now, right now
juxta (adv) near, near by; (prep) near, near to, next to
la her
le (art) the
le (pron) him
les them
lo it; lo que: that which, what
loco place; in loco de: instead of; in su loco: instead
longe far; away, far away; de longe: from afar, from a distance
lontan distant, far-off
lor their
lore their
ma but; no solo ... ma anque: not only ... but also
malgrado in spite of
maniera manner, way; de maniera que: so that
me me
melio (adv) better; tanto melio: so much the better
melior (adj) better; le melior: the best
mesme same; myself, yourself, himself, etc. (as in "the king himself")
mesmo likewise; even; hodie memso: this very day; ora mesmo: right now
mi my
mie mine
minus less; minus; a minus que: unless; al minus: at least; totos minus ille: all but him; le minus: the least
multo very; much
nam for
nemo no one, nobody
ni neither, no, also not
nihil, nil nothing
nimie (adj) too much, too many
nimis (adv) too, too much
no (adv) no
non not; no; si non: if not; except; unless it be
nondum not yet
nonne (interr part) is it not?; il es ver, nonne?: it is true, isn't it?
nonobstante (prep) despite, in spite of; (adv) nevertheless
nos us, we
nostre our, ours
nulle (adj) not any, no; null, worthless, without legal force
nullemente in no way, not at all
nunc now
nunquam never
nusquam nowhere
o or; o ... o: either ... or
olim once, formerly; at a future time, sometime (in the future)
omne (adj) all; each, every; de omne mano: from every hand; de omne latere: from every side; in omne caso: in any case; omne cosa: everything; omnes: (pron) all
on one
ora now
parte part; a parte: apart, aside; in parte: in part; del parte de: on the part of; de parte a parte: through and through; in nulle parte: nowhere
passato ago
pauc (adj) little, not much; few; un pauc (de): a little; pauc a pauc: little by little; in pauc: shortly, before long
pauco (adv) little
per through; during, throughout; by, through, by means of; per
perque (adv/conj) why; because
plus more; plus; le plus: the most; de plus: furthermore, besides; de plus in plus: more and more; in plus: furthermore, in addition, also; al plus: at best; plus o minus: more or less; non ... plus: no more; no longer
pois (adv) afterwards, thereafter; (conj) for; pois que: since, as, because
post (adv) behind, back, backwards; afterwards, after; (prep) behind; after; post que: since, because
postea afterwards, thereafter
postquam (conj) after; as soon as
potius rather, sooner
presso (adv/prep) near, close; a presso de: at the home of; in care of; with, among
presto presto, quickly, quick as a wink
preter (adv) past, beyond; (prep) past, along, alongside of; beyond; except, excepting; in addition to
pridem long ago
pro for, in favor of; in exchange for, in place of; pro (+inf): (in order) to
proque (adv/conj) why; because
qual which; what; le qual: which; that; who
qualcunque any, whatever
quando (adv/conj) when
quandocunque whenever
quante (adj) how much, how many
quanto (adv) as much as; as far as; quanto ... tanto: the ... the; quanto a: as for
quare wherefore, why
quasi almost, nearly; in a certain sense, in a way; quasi que: as if
que (interr pron) what; (rel pron) who, whom, which, that
que (conj) 1. that; 2. than
qui who, whom; de qui: whose
quia because, for
quicunque whoever, whomever, whosoever
quo (adv) whither, where; wherefore; (conj) so that, in order that
re about, concerning
retro back, backwards; ago; a retro: backwards
salvo save, but, but for; salvo que: save that, but that
satis enough; rather, somewhat; esser satis: to be enough; haber satis: to have enough; satis de (tempore, etc.): enough (time, etc.)
se (refl pron) himself; herself; itself; themselves
secundo (prep) (following) after; along, by; according to; secundo que: according as
sed but
semper always
si (adv) thus, so; yes; si ... como: as ... as
si (conj) if; whether; si non: if not; except, unless it be
sia be, may be, let there be; sia ... sia: be (it) ... or be (it); whether ... or; qual que sia: whatever, whatsoever
sin (prep) without
sol (adj) sole, alone, only; viver sol: to live alone; sentir se sol: to feel lonesome, lonely
solo (adv) only, merely; non solo ... ma anque: not only ... but also
su his, her, its
sub (prep) under, below, beneath
subinde immediately after, just after, forthwith; repeatedly, frequently, often, from time to time
subito suddenly, unexpectedly
subtus (adv) below, beneath, underneath
sue his, hers, its
super (prep) on, upon; on top of; over, above; about, concerning, on; (adv) above, on top; super toto: above all
supra (prep) above, over; (adv) on the top, above
sur on, upon; on top of
tal such, such a; tal e tal: such and such
talmente (adv) so; un libro talmente belle: so beautiful a book, such a beautiful book
tamen yet, however, nevertheless, notwithstanding
tante (adj) so much, so many; tante per cento: so much per hundred, percentage; tante ... como: as much, as many ... as
tanto (adv) so, so much; tanto ... como: as much ... as; in tanto que: inasmuch as; tanto plus ... que: all the more ... that; quanto ... tanto: the ... the
tarde (adv) late; plus tarde: later; later on; al plus tarde: at the latest
te you, thee; yourself, thyself
tosto presently, soon, promptly; plus tosto: rather, sooner; si tosto que: as soon as
tote (adj) all; every, each; tote le (homines): all (men); totos: all, everyone; de tote (le) corde: wholeheartedly; tote (le) duo: both
totevia yet, still, nevertheless
toto (n) all, everything; le toto: the whole; super toto: above all; ante toto: before all; post toto: after all; del toto: at all; in toto: entirely, wholely, in toto
toto (adv) all, quite, wholely
trans across, over, beyond, on the farther side of
troppo too, too much; troppo (de) (libros, etc.): too many (books, etc.); troppo (de) (aqua, etc.): too much (water, etc.); de troppo: superfluous, in the way, de trop
tu your, thy
tue yours, thine
tunc then
ubi (adv) where; (conj) where; when; as soon as; wherewith; in which; a ubi: where, whither; de ubi: from where, whence
ubicunque wherever
ubique everywhere; anywhere, wheresoever, wherever
ultra (adv) on the other side, beyond, farther; (prep) on the farther side of; beyond, past; besides; ultra illo: besides, moreover; ultra que: aside from the fact that
un a, an; le un le altere: one another, each other; le unes les alteres: one another, each other
uno (indef pron) one
unquam ever, at any time
usquam somewhere
usque (prep) (all the way up) to, up to; till, until; usque nunc: up to now
verso towards, to
via (adv) away; off; via!: go away!, begone!; (prep) by way of, via
vice (n) turn, stead; time (as in "three times"); alicun vices: sometimes; un vice: once; on one occasion; formerly; un vice que: once, once that; in vice de: instead of; a vices: at times; altere vice: a second time; plure vices: several times, repeatedly
viste considering; viste que: considering that
vix adv 1. with difficulty; 2. hardly, scarcely, barely
voluntarie willingly, readily, gladly, with pleasure
vos you; yourself, yourselves
vostre your, yours
ya (adv) indeed, certainly, of course; ya (io lo crede): (I) do (believe it)

Word Building

Nouns derived from Nouns

-ada 1. 'product made from ...'; 2. 'series of ...'
-age (pronun. -aje) 'collection of ...' (NOTE: -agi- before -a- or -o- of additional suffix)
-alia 'worthless collection of ...'
-ano 1. 'native, citizen, or inhabitant of ....'; 2. 'language of ...'; 3. 'adherent or follower of ...' (fem. -ana in senses 1,3) (NOTE: used with names of places and persons. In the case of place names not ending in -a or -o as also of all names of persons, the euphonic variant -iano is to be preferred.)
-ario I. 'person concerned with or characterized by ...'; II. 1. 'collection of ...'; 2. 'place containing ...'
-astro 1. 'inferior or worthless ...'; 2. 'related through remarriage of a parent' (fem. -astra)
-ata 'contents of or quantity contained in one ...'
-ato 'function, status, rank, jurisdiction, period of office, or territory of a ...'
-eria (pronun. -erķa) 1. 'place where ... is made, worked, kept, or sold'; 2. 'art, craft, trade, or practice of working with ...'; 3. 'behavior of a ... or like that of a ...'
-ero 'one who works with or deals in ...'
-ese 1. 'native, citizen, or inhabitant of ...'; 2. 'language of ...'
-essa 1. 'female ...'; 2. 'wife of a ...'
-eto 'grove of ... trees'
-etto, -etta 'little, small, or minor ...'
-ia (pronun. -'ia) 'country, province, or region of the ...s, or named for' (NOTE: used with names of peoples and persons.)
-ia (pronun. -ķa) 1. 'state, quality, status, or jurisdiction of (a, an) ...' 2. 'art, science, or practice, also profession, establishment, etc. of (a, an) ...' (NOTE: used mostly with compounds.)
-ica 'science or study of the ...'
-ico 'one skilled in the art or science of ...'
-iera 1. 'that which contains, covers, or protects ...'; 2. 'field, mine, quarry, etc. where ... grows or is found'
-iero 'tree, bush, plant, etc. bearing or producing ...'
-il 'place where ...s are kept' (NOTE: used with names of animals.)
-ina 'substance made from, characterizing, related to, etc. ...' (NOTE: used mostly as technical [chemical] suffix.)
-ismo 1. 'state or practice of being a ...'; 2. [Med.] ' abnormal condition resulting from excess of ...'; 3. 'doctrine or practice of, or concerned with ...'; 4. 'something characteristic of ..., or of the language of ...'
-ista 1. 'one who practices the art or science of ...'; 2. 'adherent of the doctrine of...'
-ita 1. 'inhabitant, citizen, or native of ...'; 2. 'member, adherent, or partisan of ...'
-ite 'rock or other mineral containing ..., resembling ..., characterized by ..., related to ...' (NOTE: used mostly in technical [mineralogical] terms.)
-itis 'inflammatory disease of the ...' (NOTE: used with names of parts of the body, chiefly in technical [medical] terms.)
-oide 'something like, or shaped like ...'
-osis 'abnormal or diseased condition, state, or process of the ..., caused by ..., characterized by ..., etc.' (NOTE: used chiefly in technical [medical] words.)

Adjectives derived from Nouns

-al 'pertaining to ..., characteristic of ..., etc.'
-an 'pertaining to ...'; esp. 'native of ...' (NOTE: used with names of places and persons. In the case of place names not ending in -a or -o as also of all names of persons, the euphonic variant -ian is to be preferred.)
-ari 'pertaining to ..., consisting of ..., etc.'
-ate 'having a ... or ...s'
-esc 1. 'like, similar to, or characteristic of a ...'; 2. 'in the manner or style of ...'
-ese 'pertaining to'; esp. 'native to ..., of ...' (NOTE: used with names of places.)
-ic 'of, pertaining to ..., characterized by ...'
-ifere 'bearing, producing, yielding'
-ific 'making, causing ...'
-in 'of, pertaining to, etc., ...' (NOTE: used particularly with names of animals.)
-ista pertaining to ...ism or ...ists' (NOTE: not distinct from nouns in apposition.)
-oide 'like ..., shaped like ...' (NOTE: used chiefly in technical term.)
-ose 'having, abounding in ..., characterized by' (NOTE: -ion plus -ose > -iose.)
-otic 'pertaining to ...osis'

Verbs derived from Nouns and Adjectives

-ar 1. 'to make use of ....; to apply, give, etc. ...'; 2. 'to render ..., to make ..., etc.'
-ificar 'to make, render ...; to convert into ...'
-isar 1. 'to make into ...'; 2. 'to apply ...; to make use (of the principles) of ..., etc.'; 3. 'to render ..., to make'

Nouns derived from Adjectives

-essa 'state or quality of being ...'
-ia (pronun. -'ia) 'state or quality of being ...' (NOTE: used chiefly with adjectives in -nte.)
-ia (pronun. -ķa) 'state or quality of being ...' (NOTE: used chiefly with technical compounds.)
-ismo 1. 'state or quality of being ...'; 2. 'doctrine or practice concerned with what is ...'; 3. 'something characteristic of the ... people or of their language'
-ista 'adherent of the doctrine or practice concerned with what is ...'
-itate 'state or quality of being ...' (NOTE: synonym of -itude, but preferred when the base is already a derivative.)
-itude 'state or quality of being ...'

Adjectives derived from Adjectives

-ette 'somewhat ...; pretty ...'

Derivations from Verbs

-ada (n) 'continued or prolonged action of'
-age (n) 'action or process of'
-eria (n) 1. 'place where ... is done'; 2. 'art, craft, trade, or practice of; also: the product of such work'
-amento (-ar), -imento (-er, -ir) (n) 'action or result of'
-ante (-ar), -ente (-er), iente (-ir) (adj) ', that ...s' (NOTE: identical with present participle.)
-ante (-ar), -ente (-er), -iente (-ir) (n) 'one who or that which is or ...s'
-antia (-ar), -entia (-er), -ientia (-ir) (n) 'state or quality of'
-abile (-ar), -ibile (-er, -ir) (adj) 'that can be ...ed; that is worthy to be ...ed'
-ation (-ar), -ition (-er, -ir) (n) 'action or result of'
-ative (-ar), -itive (-er, -ir) (adj) 1. 'tending to ...'; 2. 'having the function of'
-ator (-ar), -itor (-er, -ir) (n) 'one who, or that which ...s'
-atori (-ar), -itori (-er, -ir) (adj) 'pertaining to, or serving for, the action of'
-atorio (-ar), -itorio (-er, -ir) (n) 'place where, installation or instrument with which is done'
-atrice (-ar), -itrice (-er, -ir) (n) 'a woman who ...s'
-atura (-ar), itura (-er, -ir) (n) 'action or result of'
-ate (-ar), -ite (-er, -ir) (adj) 1. '...ed, being ...ed'; 2. '...ed, having ...ed (NOTE: identical with the past participle.)

General Prefixes

ad- (v) 'to, toward, into' (NOTE: by extension, 'change into, increase of intensity, etc.'.)
ante- (n, adj, v) 'preceding in time or space'
anti- (n, adj) opposed to, against; opposite' (NOTE: ant- before 'h' and vowels.)
auto- (n, adj) 'self' (NOTE: aut- before vowels.)
circum- (adj, v) 'about, around'
co- (n, adj) 'joint, fellow'
con- (n, adj, v) 'with, together, jointly, mutually' (NOTE: 'n-' mutates under certain conditions.)
contra- (n, v) 'against, opposing; counter or contrary to'
dis- (n, adj, v) 1. 'apart, separately; divided, scattered'; 2. 'not ..., contrary or opposite of'
ex- (n) 'former'
extra- 1. (n, adj, v) 'outside; outside the scope of'; 2. (adj) 'highly, unusually, very'
gran- (in names of kinship) 'grand-, great-' (NOTE: for further reduplication, the prefix 'pro-' is available.)
in- I. (v) 'in, into'; II. (n, adj) 'not ...; lacking; lack of' (NOTE: 'n-' mutates under certain conditions.)
inter- (n, adj, v) 'between, among'
intra- (adj) 'inside, within'
intro- (v) 'inwards, to the inside'
mis- (v) 'badly, wrongly'
non- (n, adj) 'not ..., lack or absence of'
per- (v) 1. 'through, throughout'; 2. 'thoroughly, extremely, very'
post- (n, adj, v) 'behind, after in time, location, or order'
pre- (n, adj, v) 'before in time, position, or rank'
pro- 1. (n, adj) 'in favor of, on the side of'; 2. (v) 'forward, forth'
re- (v) 1. 'back, backwards'; 2. 'again'
retro- (v) 'back, backwards'
sub- (n, adj, v) 1. 'under, underneath'; 2. 'subordinate; subdivision of'; 3. 'slightly, slight' (NOTE: 'b-' mutates under certain conditions.)
super- (n, adj, v) 1. 'over, above'; 2. 'very; excessively, too much'
trans- (n, adj, v) 1. 'beyond, across; surpassing' 2. 'though, across'
ultra- (n, adj, v) 'beyond'
vice- (n) 'one who takes the place of'

Technical Prefixes (modifying nouns and adjectives)

a- 'not ...; without ...; lacking ...' (NOTE: an- before 'h' and vowels.)
amphi- 1. 'both, on both sides'; 2, 'around, about'
ana- 'again'
apo- 1. 'off, away'; 2. [Chem.] 'formed from, related to'
cata- 1. 'down, downwards'; 2. 'against, reflected' (NOTE: cat- before 'h' and vowels.)
dia- 1. 'through'; 2. 'away, apart' (NOTE: di- before vowels.)
dys- 'bad, badly, not well'
ecto- 'outside, external' (NOTE: ect- before vowels.)
en- 'in, into' (NOTE: em- before, 'b', 'm', 'p', 'ph'.)
endo- 'within' (NOTE: end- before vowels.)
ento- 'within, inside' (NOTE: ent- before vowels.)
epi- 'on, upon' (NOTE: ep- before 'h' and vowels.)
exo- 'without, outside' (NOTE: ex- before vowels.)
hyper- 'over; beyond; too much'
hypo- 1. 'below, beneath, under'; 2. 'to a lower degree; somewhat'; 3. [Chem.] 'indicating a lower state of oxidation, or a lower position in a series of compounds'
meta- 1. 'behind'; 2. 'beyond, transcending, higher'; 3. 'after, subsequent to' (NOTE: met- before 'h' and vowels.)
para- 1. ' besides, alongside'; 2. 'amiss, faulty, wrong'; 3. 'resembling; modification of' (NOTE: par- before 'h' and vowels.)
peri- 'around, about'
syn- 'with, together; alike' (NOTE: syl- before 'l'; sym- before 'b', 'm', 'p', and 'ph'.)

(NOTE: the Interlingua Grammar, pp.78ff [§161], lists a number of affixes, many derived from Greek (a few from Latin), which may also be used in word building and which are similar to their use in English and many of the west European languages, especially in technical and scientific compounds.)