pawnbroker n.

"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."

mid-14c. (mid-13c. in surnames), "commercial agent, factor," also "an agent in sordid business," from Anglo-French brocour "small trader," from abrokur "retailer of wine, tapster;" perhaps from Portuguese alborcar "barter," but more likely from Old French brocheor, from brochier "to broach, tap, pierce (a keg)," from broche (Old North French broke, broque) "pointed tool" (see broach (n.)), with an original sense of "wine dealer," hence "retailer, middleman, agent." In Middle English, used contemptuously of peddlers and pimps, "one who buys and sells public office" (late 14c. in Anglo-French), "intermediary in love or marriage" (late 14c.).