Meaning

noun (sports) a division during which one team is on the offensive

noun a period of illness

noun a contest or fight (especially between boxers or wrestlers)

originFrom Middle English bout, bowt, bught (whence also modern English bought (“bend, curve”)), probably from Old English *buht (“bend, turn”), an unrecorded variant of Old English byht (“a bend, curve”), from Proto-West Germanic *buhti, from Proto-Germanic *buhtiz (“a bend”). Equivalent to bow + -t. Doublet of bight and bought. For the sense development compare bender.

Etymology from Wiktionary, CC BY-SA 3.0