I

Id certum es um reddi potest t quod cert - That is certain that can be made certain
Id est mihi, id non est tibi! - It is mine, not yours!
Id imperfectum manet dum confectum erit - It ain't over until it's over
Id tibi praebet speciem lepidissimam! - It looks great on you!
Idem quod (i.q.) - The same as
Idem - The same
Iesus Nazarenus Rex Iudaeorum (INRI) - Jesus of Nazareth, King of the Jews
Ignis aurum probat, miseria fortes viros - Life is not a bowl of cherries, or, literally, Fire tests gold; adversity tests strong men
Ignis fatuus - Foolish fire (will-o-the-wisp)
Ignorantia juris neminem excusat - Ignorance of the law excuses no one
Ignoratio elenchi - An ignorance of proof
Ignotus (ign.) - Unknown
Ille dolet vere, qui sine teste dolet - He mourns honestly who mourns without witnesses. (Martialis)
Ille mi par esse deo videtur - He seems to me to be equal to a god. (Catullus)
Illegitimis nil carborundum - Don't let the bastards grind you down
Illiud latine dici non potest - You can't say that in Latin
Illius me paenitet, dux - Sorry about that, chief
Imitatores, servum pecus! - Imitators, you slavish crowd! (Horace)
Imperator/Imperatrix (Imp.) - Emperor/Empress
Imperator - Emperor
Imperium et libertas - Empire and liberty. (Cicero)
Imperium in imperio - An empire within an empire, i.e. A fifth column, a group of people within an nation's territory who owe allegiance to some other leader
Imperium - Absolute power
Impossibilium nulla obligatio est - Nobody has any obligation to the impossible. (Corpus Iuris Civilis)
Imprimatur - Let it be printed
Imprimis - In first place
In absentia - In one's absence
In actu - In practice
In aere aedificare - Build (castles) in the air. (St. Augustine)
In aeternum - For eternity
In alio pediculum, in te ricinum non vides - You see a louse on someone else, but not a tick on yourself. (Petronius)
In articulo mortis - At the moment of death
In banco - On the bench
In camera - In private chamber
In capite - In chief
In cavda venenvm - In the tail [is the] poison. Watch out for what you don't see
In curia - In court
In dentibus anticis frustrum magnum spiniciae habes - You have a big piece of spinach in your front teeth
In distans - At a distance
In dubiis non est agendum - In dubious cases, you should not act
In dubio pro reo - In doubt in favor of the accused. If there is a doubt about guiltiness, the judgement has to be in favour of the accused
In dubio - In doubt
In esse - In existence
In excelsis - In the highest
In extenso - At full length
In extremis - In extremity
In fine - At the end
In flagrante delicto - In the very act of committing an offence
In forma pauperis - In the form of a poor person; in a humble or abject manner
In futuro - In the future
In gremio legis - In the protection of the law
In his ordo est ordinem non servare - In this case the only rule is not obeying any rules
In hoc signo vinces - In this sign, you will be victorious. (Eusebios)
In infinitum - To infinity; without end
In libris libertas - In books (there is) freedom
In limine - On the threshold, at the very outset
In loco parentis - In the place of a parent
In loco - In the place of
In magnis et voluisse sat est - To once have wanted is enough in great deeds. (Propertius)
In media res - In or into the middle of a sequence of events. (Horace)
In medias res - Into the midst of things
In medio stat virtus - Virtue stands in the middle. Virtue is in the moderate, not the extreme position. (Horace)
In medio tutissimus ibis - In the middle of things you will go most safe. (Ovid)
In memoriam - To the memory of
In necessariis unitas, in dubiis libertas, in omnibus caritas - In necessary things unity, in doubtful things liberty, in all things charity
In nomine Domini - In the name of the Lord
In nomine Patris et Filii et Spiritus Santi - In the name of the Father and of the Son and of the Holy Spirit
In nubibus - In the clouds
In nuce - In a nutshell
In omnia paratus - Prepared for all things
In ovo - In the egg
In pace, ut sapiens, aptarit idonea bello - In peace, like a wise man, he appropriately prepares for war
In pace - In peace
In pari materia - Of like kind
In partibus infidelium - In parts inhabited by unbelievers
In parvo - In miniature
In perpetuum - For ever
In personam - Against the person
In pleno - In full
In pontificalibus - In the proper vestments of a pope or cardinal
in posse - In possibility
In posterum - Till the next day
In praesenti - At the present time
In principio - In the beginning
In propria persona - In person
In puris naturalibus - Completely naked
In quaestione versare - To be under investigation
In re - Refering to
In rem - Against the matter (property)
In rerum natura - In the nature of things
In saecvla saecvlorvm - For ages of ages forever
In se - In itself
In silico - By means of a computer simulation
In silvam ne ligna feras - Don't carry logs into the forest. (Horace)
In situ - In position
In specie - In kind; (a) in its own form and not in an equivalent (b) in coins and not in paper money
In spiritu et veritate - In spirit and truth. (Versio Vulgata)
In statu quo - In the same state
In terrorem - As a warning; in order to terrify others
In totidem verbis - In so many words
In toto - As a whole, absolutely, Completely
In transitu - In passing, on the way
In usu - In use
In utero - In the womb
In vacuo - In a vacuum or empty space
In vinculis etiam audax - In chains yet still bold (free)
In vino veritas - The truth is in wine. (A drunk person tells the truth)
In virtute sunt multi ascensus - There are many degrees in excellence. (Cicero)
In vitro - In a test tube (literally glass)
In vivo - In the living (thing)
Incipit - Begin here
Incredibile dictu - Incredible to say
Index librorum prohibitorum - Official list of forbidden books not to be read by Catholics
Indulgentiam quaeso - I ask your indulgence
Infinitus est numerus stultorum - Infinite is the number of fools
Infra dignitatem (dig.) - Undignified; beneath one's dignity
Infra - Below, underneath
Inhumanitas omni aetate molesta est - Inhumanity is harmful in every age. (Cicero)
Iniqua nunquam regna perpetuo manent - Stern masters do not reign long. (Seneca Philosophus)
Iniuria non excusat iniuriam - One wrong does not justify another
Insanabile cacoethes scribendi - An incurable passion to write. (Juvenal)
Insculpsit - He/she engraved it
Instrumentum aeri temperando - Airconditioner
Insula gilliganis - Gilligan's Island
Integer vitae scelerisque purus - Blameless of life and free from crime
Intellectum valde amat - Love the intellect strongly. (St. Augustine)
Intelligenti pauca - Few words suffice for he who understands
Intelligo me intelligere - I understand that I understand. (St. Augustine)
Inter alia - Among other things
Inter alios - Amongst other people
Inter arma silent leges - In time of war, laws are silent
Inter caecos regnat strabo - Among blinds the squinting rules. (Erasmus)
Inter caesa et porrecta - There's many a slip twixt cup and lip
Inter canum et lupum - Between a dog and a wolf
Inter nos - Between ourselves
Inter partes - Made between two parties
Inter se - Between themselves
Inter spem et metum - Between hope and fear
Inter vivos - Between living (people)
Interdum feror cupidine partium magnarum europe vincendarum - Sometimes I get this urge to conquer large parts of Europe
Interfice errorem, diligere errantem - Kill the sin, love the sinner. (St. Augustine)
Interregnvm - Period between rules anarchy, lawlessnes
Intra muros - Within the walls
Intra vires - Within the power
Inventas vitam iuvat excoluisse per artes - Let us improve life through science and art. (Vergil)
Ipsa qvidem pretivm virtvs sibi - Virtue is its own reward
Ipsa scientia potestas est - Knowledge itself is power. (Bacon)
Ipsi dixit - He himself said it. (Cicero)
Ipsissima verba - The exact words
Ipso facto - By that very fact
Ipso iure - By operation of the law
Ira furor brevis est - Anger is a brief insanity. (Horace)
Ire fortiter quo nemo ante iit - To boldly go where no man has gone before. (Star Trek)

Ita est - Yes./It is so
Ite, misse est - Go, the Mass is finished
Iubilate Deo - Rejoice in God
Iunctis viribus - By united efforts
Iure divino - By divine law
Iure humano - By human law
Ius civile - Civil law
Ius gentium - The law of nations
Ius primae noctis - The right of the first night
Ivs est ars boni et aeqvi - Law is the art of the good and the just
Ivs gentivm - Right of tribes law of nations