1530s, "social intercourse;" 1580s, "interchange of goods or property, trade," especially trade on a large scale by transportation between countries or different parts of the same country, from French commerce (14c.), from Latin commercium "trade, trafficking," from com "with, together" (see com-) + merx (genitive mercis) "merchandise" (see market (n.)). It also was the name of a card game very popular in 1770s and '80s. As a verb, "have dealings with," 1590s. Related: Commerced, commercing.
"relating to trade or commerce; pertaining to merchants," c. 1400, from merchant (n.) and from Old French marcheant (adj.).
mid-13c., marchaundise, "trading, commerce, action or business of buying and selling goods or commodities for profit;" mid-14c., "commodities of commerce; wares, movable objects, and articles for sale or trade," from Anglo-French marchaundise, Old French marcheandise "goods, merchandise; trade, business" (12c.), from marchaunt "merchant" (see merchant). The plural had become obsolete in English by late 19c.