"something given or deposited as security," as for money borrowed, late 15c. (mid-12c. as Anglo-Latin pandum), from Old French pan, pant "pledge, security," also "booty, plunder," perhaps from Frankish or some other Germanic source (compare Old High German pfant, German Pfand, Middle Dutch pant, Old Frisian pand "pledge"), from West Germanic *panda, which is of unknown origin.
The Old French word is formally identical to pan "cloth, piece of cloth," from Latin pannum (nominative pannus) "cloth, piece of cloth, garment" and this formerly was suggested as the source of both the Old French and West Germanic words (on the notion of cloth used as a medium of exchange), but Century Dictionary notes that "the connection seems to be forced."
"lowly chess piece, a piece of the lowest rank and value in chess," late 14c., poune, from Anglo-French poun, Old French peon, earlier pehon "a foot-soldier; a pawn at chess," from Medieval Latin pedonem "foot soldier," from Late Latin pedonem (nominative pedo) "one going on foot," from Latin pes (genitive pedis) "foot," from PIE root *ped- "foot." The chess sense was in Old French by 13c. Figurative use, of persons, is by 1580s, but Middle English had rook and pawn "high and low persons," thus "everyone."
"to give or deposit (something) as security" in exchange for the payment of money borrowed, etc., 1560s, from pawn (n.1). Related: Pawned; pawning.