late 14c., "young of the coney," from Walloon robète or a similar French dialect word, diminutive of Flemish or Middle Dutch robbe "rabbit," of unknown origin. "A Germanic noun with a French suffix" [Liberman]. The adult was a coney (q.v.) until 18c.

Zoologically speaking, there are no native rabbits in the United States; they are all hares. But the early colonists, for some unknown reason, dropped the word hare out of their vocabulary, and it is rarely heard in American speech to this day. When it appears it is almost always applied to the so-called Belgian hare, which, curiously enough, is not a hare at all, but a true rabbit. [Mencken, "The American Language"]

Rabbit punch "chop on the back of the neck" so called from resemblance to a gamekeeper's method of dispatching an injured rabbit. Pulling rabbits from a hat as a conjurer's trick recorded by 1843. Rabbit's foot "good luck charm" first attested 1879, in U.S. Southern black culture. Earlier references are to its use as a tool to apply cosmetic powders.

[N]ear one of them was the dressing-room of the principal danseuse of the establishment, who was at the time of the rising of the curtain consulting a mirror in regard to the effect produced by the application of a rouge-laden rabbit's foot to her cheeks, and whose toilet we must remark, passim, was not entirely completed. [New York Musical Review and Gazette, Nov. 29, 1856]

Rabbit ears "dipole television antenna" is from 1950. Grose's 1785 "Dictionary of the Vulgar Tongue" has "RABBIT CATCHER. A midwife."

iron bar for stirring molten metal, 1864, from French râble, from Old French roable, from Latin rutabulum "rake, fire shovel," from ruere to rake up (perhaps cognate with Lithuanian rauju, rauti "to pluck out," German roden "to root out").

1842, agent noun from Rabble-rousing, which is attested by 1802 in Sydney Smith; from rabble (n.1) + rouse.

1817, from 16c. French author François Rabelais, whose writings "are distinguished by exuberance of imagination and language combined with extravagance and coarseness of humor and satire." [OED]