What is the Latin word for unacceptable?

The usual Latin words for “unacceptable” are iniūcundus, ingrātus, īnsuāvis. The right choice depends on the sense; see the distinctions below.

English → Latin

“unacceptable” in Latin

iniūcundusunpleasant, disagreeable ingrātusunpleasant, disagreeable; thankless; ungrateful īnsuāvisunpleasant, disagreeable

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

unacceptable

*quod alicui gratum acceptumque non est; or injucundus: ingratus: insuavis. Vid: UNPLEASANT.

Quick answer

What is the Latin word for unacceptable?: The usual Latin words for “unacceptable” are iniūcundus, ingrātus, īnsuāvis. 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.