late 14c., pusillanimite, "timidity, faint-heartedness," from Old French pusillanimité (14c.) and directly from Church Latin pusillanimitatem (nominative pusillanimitas) "faintheartedness," from Latin pusillanimis "fainthearted, having little courage" (see pusillanimous).

"cat," 1520s, but probably much older than the record, perhaps imitative of the hissing sound commonly used to get a cat's attention. A conventional name for a cat in Germanic languages and as far off as Afghanistan; it is the root of the principal word for "cat" in Rumanian (pisica) and secondary words in Lithuanian (puž, word used for calling a cat), Low German (puus), Swedish dialect katte-pus, etc. Applied to a girl or woman from c. 1600, originally in a negative sense, implying unpleasant cat-like qualities; but by mid-19c. in affectionate use.

slang for "female pudenda," 1879, but probably older; perhaps from Old Norse puss "pocket, pouch" (compare Low German puse "vulva"), but perhaps instead from the cat word (see pussy (n.1)) on notion of "soft, warm, furry thing;" compare French le chat, which also has a double meaning, feline and genital. Earlier uses are difficult to distinguish from pussy (n.1), as in:

The word pussie is now used of a woman [Philip Stubbes, "The Anatomie of Abuses," 1583]

But the absence of pussy in Grose and other early slang works argues against the vaginal sense being generally known before late 19c., as does its frequent use as a term of endearment in mainstream literature, as in:

"What do you think, pussy?" said her father to Eva. [Harriet Beecher Stowe, "Uncle Tom's Cabin," 1852]

Pussy-whipped first attested 1956 (Middle English had cunt-beaten "impotent," in reference to a man, mid-15c.).