merchant (n.) Look up merchant at Dictionary.com
c. 1200, from Anglo-French marchaunt "merchant, shopkeeper" (Old French marcheant, Modern French marchand), from Vulgar Latin *mercatantem (nominative *mercatans) "a buyer," present participle of *mercatare, frequentative of Latin mercari "to trade, traffic, deal in" (see market). Meaning "fellow, chap" is from 1540s; with a specific qualifier, and suggesting someone who deals in it (such as speed merchant "one who enjoys fast driving"), from 1914.
merchant (adj.) Look up merchant at Dictionary.com
c. 1400, from merchant (n.) and from Old French marcheant (adj.).