open-air game involving kicking a ball, c. 1400; in reference to the inflated ball used in the game, mid-14c. ("Þe heued fro þe body went, Als it were a foteballe," Octavian I manuscript, c. 1350), from foot (n.) + ball (n.1). Forbidden in a Scottish statute of 1424. One of Shakespeare's insults is "you base foot-ball player" [Lear I.iv]. Ball-kicking games date back to the Roman legions, at least, but the sport seems first to have risen to a national obsession in England, c. 1630. Figurative sense of "something idly kicked around, something subject to hard use and many vicissitudes" is by 1530s.
Rules of the game first regularized at Cambridge, 1848; soccer (q.v.) split off in 1863. The U.S. style (known to some in England as "stop-start rugby with padding") evolved gradually 19c.; the first true collegiate game is considered to have been played Nov. 6, 1869, between Princeton and Rutgers, at Rutgers, but the rules there were more like soccer. A rematch at Princeton Nov. 13, with the home team's rules, was true U.S. football. Both were described as foot-ball at Princeton.
Then twenty-five of the best players in college were sent up to Brunswick to combat with the Rutgers boys. Their peculiar way of playing this game proved to Princeton an insurmountable difficulty; .... Two weeks later Rutgers sent down the same twenty-five, and on the Princeton grounds, November 13th, Nassau played her game; the result was joyous, and entirely obliterated the stigma of the previous defeat. ["Typical Forms of '71" by the Princeton University Class of '72, 1869]
c. 1200, from Old English gamen "joy, fun; game, amusement," common Germanic (cognates: Old Frisian game "joy, glee," Old Norse gaman "game, sport; pleasure, amusement," Old Saxon gaman, Old High German gaman "sport, merriment," Danish gamen, Swedish gamman "merriment"), said to be identical with Gothic gaman "participation, communion," from Proto-Germanic *ga- collective prefix + *mann "person," giving a sense of "people together."
The -en was lost perhaps through being mistaken for a suffix. Meaning "contest for success or superiority played according to rules" is first attested c. 1200 (of athletic contests, chess, backgammon). Especially "the sport of hunting, fishing, hawking, or fowling" (c. 1300), thus "wild animals caught for sport" (c. 1300), which is the game in fair game (see under fair (adj.)), also gamey. Meaning "number of points required to win a game" is from 1830. Game plan is 1941, from U.S. football; game show first attested 1961.
early 13c., "a clasping, an embracing," verbal noun from clip (v.2). As a U.S. football penalty (not in OED), from 1920.
Clipping or Cutting Down from Behind. — This is to be ruled under unnecessary roughness, and penalized when it is practiced upon "a man obviously out of the play." This "clipping" is a tendency in the game that the committee is watching anxiously and with some fear. [Collier's, April 10, 1920]