late 14c., "feminine quality, womanliness, female nature," femynynytee, from feminine + -ity. From 1832 as "women collectively;" from 1853 as "character or state of being state of being a woman."
Entries linking to femininity
feminine adj.
mid-14c., "of the female sex," from Old French femenin (12c.) "feminine, female; with feminine qualities, effeminate," from Latin femininus "feminine" (in the grammatical sense at first), from femina "woman, female," literally "she who suckles" (from PIE root *dhe(i)- "to suck"). The usual modern sense of "woman-like, proper to or characteristic of women" is recorded from mid-15c. Related: Femininely.
The interplay of meanings now represented roughly in female "characteristic of the sex that bears children," feminine "having qualities considered appropriate to a woman," and effeminate "having female qualities in a bad sense, unmanly," and the attempt to keep them clear of each other, has led to many coinages. Among nouns, in addition to feminity "womanishness," femininity, femaleness, feminineness (1810, "female qualities"), there is feminitude (1878); feminility "womanliness" (1824); feminie "womankind" (late 14c.); femality (17c., "effeminacy;" 1754 "female nature"); feminacy "female nature" (1829); feminicity "quality or condition of being a woman" (1843). Also feminality (1640s, "quality or state of being female"), from rare adjective feminal "female, belonging to a woman" (late 14c.), from Old French feminal. And femineity "quality or state of being feminine," also "effeminate; womanly," from Latin femineus "of a woman, pertaining to a woman." feminile "feminine" (1640s) seems not to have survived.
-ity
word-forming element making abstract nouns from adjectives and meaning "condition or quality of being ______," from Middle English -ite, from Old French -ete (Modern French -ité) and directly from Latin -itatem (nominative -itas), suffix denoting state or condition, composed of -i- (from the stem or else a connective) + the common abstract suffix -tas (see -ty (2)).
Roughly, the word in -ity usually means the quality of being what the adjective describes, or concretely an instance of the quality, or collectively all the instances; & the word in -ism means the disposition, or collectively all those who feel it. [Fowler]