broker (n.) Look up broker at Dictionary.com
late 14c., 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 "pointed tool" (see broach (n.)), giving original sense of "wine dealer," hence "retailer, middleman, agent." In Middle English, used contemptuously of peddlers and pimps.
broker (v.) Look up broker at Dictionary.com
1630s (implied in brokering), from broker (n.). Related: Brokered.