mid-14c., pelot, "any little ball," as of a medicine or food, but especially a little metallic ball used as a missile, from Old French pelote "small ball" (11c.) and directly from Medieval Latin pelotis, from Vulgar Latin *pilotta, diminutive of Latin pila "ball, playing ball, the game of ball," perhaps originally "ball of hair," from pilus "hair" (see pile (n.3)).
1630s, "a small body of soldiers acting together but separate from the main body of troops," from French peloton "platoon, group of people," literally "little ball" (15c.), hence, "agglomeration," diminutive of Old French pelote "ball" (see pellet). Football sense of "group of players trained to act as a unit on the field" is by 1941.
"to strike repeatedly" (with something), c. 1500, a word of unknown origin; according to one old theory it is perhaps from early 13c. pelten "to strike," a variant of pilten "to thrust, strike," from an unrecorded Old English *pyltan, from Medieval Latin *pultiare, from Latin pultare "to beat, knock, strike," or [Watkins] pellere "to push, drive, strike" (from PIE root *pel- (5) "to thrust, strike, drive"). OED doubts this. Or it might be from Old French peloter "to strike with a ball," from pelote "ball" (see pellet (n.)) [Klein].
From 1680s as "to go on throwing (missiles) with intent to strike." The meaning "proceed rapidly and without intermission" (1831) is from the notion of beating the ground with rapid steps. Related: Pelted; pelting.
1749, "two-edged, heavy broadsword of ancient Scottish Highlanders," from Gaelic claidheamh mor "great sword," from claidheb "sword" (compare Welsh cleddyf), which is possibly from a PIE root *kel- "to strike" (see holt) + mor "great" (compare Welsh mawr; see more).
An antiquarian word made familiar again by Scott's novels. It was sometimes applied inaccurately to 16c.-18c. one-handed basket-hilted broad swords. Modern military application to a type of pellet-scattering anti-personnel mine is first attested 1962.