1680s, dim. of Scottish dialectal bun, pet name for "rabbit," previously (1580s) for "squirrel," and also a term of endearment for a young attractive woman or child (c.1600). Ultimately it could be from Scottish bun "tail of a hare" (1530s), or from Fr. bon, or from a Scandinavian source. The Playboy Club hostess sense is from 1960. The Bunny Hug (1912), along with the foxtrot and the Wilson glide, were among the popular/scandalous dances of the ragtime era.
"great hunter," 1712, in ref. to the biblical son of Cush, referred to (Gen. x.8-9) as "a mighty hunter before the Lord." It came to mean "geek, klutz" by 1983 in teenager slang, for unknown reasons. (Amateur theories include its occasional use in "Bugs Bunny" cartoon episodes featuring rabbit-hunting Elmer Fudd as a foil; its possible ironic use, among hunters, for a clumsy member of their fraternity; or a stereotype of deer hunters by the non-hunting population in the U.S.)
late 13c., from O.Fr. coton, ult. (via Prov., It., or O.Sp.) from Arabic qutn, perhaps of Egyptian origin. Philip Miller of the Chelsea Physic Garden sent the first cotton seeds to American colony of Georgia in 1732. Cotton-picking was first recorded in a Bugs Bunny cartoon, but the noun meaning "contemptible person" dates to around 1919, probably with racist overtones that have faded over the years. Cotton gin is recorded from 1794.
1776, from Hindi jangal "desert, forest, wasteland, uncultivated ground," from Skt. jangala-s "arid, sparsely grown with trees," of unknown origin. Specific sense of "land overgrown by vegetation in a wild, tangled mass" is first recorded 1849; meaning "place notoriously lawless and violent" is first recorded 1906, from Upton Sinclair's novel (cf. asphalt jungle, 1949; blackboard jungle, 1954). Jungle gym was a trademark name, 1923, by Junglegym Inc., Chicago, U.S. Jungle bunny, derogatory for "black person," attested from 1966.