masculine vs mannish

masculine is a noun but mannish is not a noun.

Word	Noun	Adjective	Verb	Adverb
masculine	Yes	Yes	No	No
mannish	No	Yes	No	No

masculine (noun)	mannish (noun)
a gender that refers chiefly (but not exclusively) to males or to objects classified as male

masculine (adjective)	mannish (adjective)
associated with men and not with women	characteristic of a man as distinguished from a woman
male (of grammatical gender)	resembling or imitative of or suggestive of a man rather than a woman
(music or poetry) ending on an accented beat or syllable