What is the Latin word for unbelieving?

The usual Latin words for “unbelieving” are īnfidēlis, incrēdulus, Lactantius. The right choice depends on the sense; see the distinctions below.

English → Latin

“unbelieving” in Latin

īnfidēlisunfaithful; treacherous, disloyal; unbelieving, infidel incrēdulusunbelieving, disbelieving, incredulous; disobedient LactantiusA masculine cognomen — famously held by

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

unbelieving

infidelis (ecclesiastical): obstinatus contra veritatem (Quint., 12, 1, 10): Deum nesciens (Lactantius): incredulus (with reference to a particular statement, † and post-Augustan prose, Hor., Quint.).

Quick answer

What is the Latin word for unbelieving?: The usual Latin words for “unbelieving” are īnfidēlis, incrēdulus, Lactantius. 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.