TRADE (O. Eng. trod, footstep, from tredan, to tread; in M. Eng. the forms teed, trod and trade appear, the last in the sense of a beaten track)  , originally a term meaning track or course, and so surviving in " trade-wind " (q.v.), a wind which always blows in one course; hence a way of life, business or occupation, and, specifically, the handicraft in which a man has been trained and which he makes his means of livelihood, or the mercantile business which he carries on for profit, as opposed to the liberal arts or professions . A further development of meaning makes the word synonymous with commerce, comprehending every species of exchange or dealing in commodities . See COMMERCE; BALANCE OF TRADE; FREE TRADE; PROTECTION; TARIFFS; TRADE ORGANIZATION; and also the sections dealing with trade and commerce. under the various countries .