LATIN DICTIONARYLexicon Latīnum
English → Latin

“frank” in Latin

The English word frank itself goes back to Latin francus, through Francus.

Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864

frank
liber (not checking his tongue from respect of persons, fear of consequences, etc. ☞ The “liber, ‘ if he carries his freeness of speech beyond the above meaning, becomes “maledicus;” Vid: Quint., 2, 12, 4): apertus (open, without deceit, of persons and their character; opposed to tectus): simplex (straightforward). (The words are found in this connection and order.) apertus et simplex: candidus (pure; of character): ingenuus (open, honest, as becomes a free-born man): simulationum nescius (unable to act a part). To be frank with anybody, alicui aperte, quod sentio, loqui (Cic.); se aperire or se patefacere alicui: to make a frank avowal of one’s opinion, [Vid: “I will tell you FRANKLY what I think”] (☞ memorem libertatis vocem mittere, Liv., 3, 36, does not apply to ordinary occasions). To be frank with you; Vid: “to speak FRANKLY.
frank v.
(a letter)(a letter), *nomine inscripto epistolam a vecturae pretio immunem facere (to write upon it the name of a person who can exempt it from postage): *epistolae perferendae mercedem persolvere (to pay the postage) to any place, ad locum. A letter is franked, *epistola a vecturae pretio immunis est.

Quick answer

What is the Latin word for frank?
The usual Latin words for “frank” are līber, aperiō, simplex; also candidus, ingenuus, loquor. The right choice depends on the sense; see the distinctions below.

Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.