analphabet
Analphabet (noun) means someone who does not know the alphabet, or who cannot read or write at all or very well.
Etymology
From Late Latin analphabetus (“unable to read and write; illiterate”), from Ancient Greek ἀναλφάβητος (analphábētos, “illiterate”), from ἀν- (an-, “un-”) + ἀλφάβητος (alphábētos, “alphabet”); analysable as an- + alphabet. The English word was probably influenced by cognate words in other languages such as French analphabète (adjective), German Analphabetus, Analphabet (nouns), analphabeten (adjective), Italian analfabeta (adjective, noun), analfabeto (adjective, noun), Portuguese analfabeto (adjective, noun), Spanish analfabeto (adjective, noun). The adjective was derived from the noun.