The Collaborative International Dictionary of English v.0.48:

Merchant \Mer"chant\, a.
   Of, pertaining to, or employed in, trade or merchandise; as,
   the merchant service.
   [1913 Webster]

   Merchant bar, Merchant iron or Merchant steel, certain
      common sizes of wrought iron and steel bars.

   Merchant service or Merchant marine, the mercantile marine
      of a country. --Am. Cyc.

   Merchant ship, a ship employed in commerce.

   Merchant tailor, a tailor who keeps and sells materials for
      the garments which he makes.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Merchant \Mer"chant\, v. i.
   To be a merchant; to trade. [Obs.]
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Merchant \Mer"chant\, n. [OE. marchant, OF. marcheant, F.
   marchand, fr. LL. mercatans, -antis, p. pr. of mercatare to
   negotiate, L. mercari to traffic, fr. merx, mercis, wares.
   See Market, Merit, and cf. Commerce.]
   1. One who traffics on a large scale, especially with foreign
      countries; a trafficker; a trader.
      [1913 Webster]

            Others, like merchants, venture trade abroad.
                                                  --Shak.
      [1913 Webster]

   2. A trading vessel; a merchantman. [Obs.] --Shak.
      [1913 Webster]

   3. One who keeps a store or shop for the sale of goods; a
      shopkeeper. [U. S. & Scot.]
      [1913 Webster]

WordNet (r) 3.0 (2006):

merchant
    n 1: a businessperson engaged in retail trade [syn: merchant,
         merchandiser]

Moby Thesaurus II by Grady Ward, 1.0:

60 Moby Thesaurus words for "merchant":
   agent, baron, broker, business, businessman, caterer, chandler,
   commercial, commissariat, commissary, dealer, distributor, donor,
   drummer, forwarder, furnisher, hawker, huckster, importer,
   industrial, industrialist, jobber, magnate, manciple, marketer,
   mercantile, merchandiser, merchant prince, middleman, mogul,
   monger, patron, provider, provisioner, purveyor, quartermaster,
   regrater, retail, retail dealer, retail merchant, retailer, seller,
   shopkeeper, steward, stock clerk, storekeeper, supplier, sutler,
   trade, trader, tradesman, tradeswoman, trading, trafficker, tycoon,
   vendor, victualer, vivandier, wholesale, wholesaler



Easton's 1897 Bible Dictionary:

Merchant
   The Hebrew word so rendered is from a root meaning "to travel
   about," "to migrate," and hence "a traveller." In the East, in
   ancient times, merchants travelled about with their merchandise
   from place to place (Gen. 37:25; Job 6:18), and carried on their
   trade mainly by bartering (Gen. 37:28; 39:1). After the Hebrews
   became settled in Palestine they began to engage in commercial
   pursuits, which gradually expanded (49:13; Deut. 33:18; Judg.
   5:17), till in the time of Solomon they are found in the chief
   marts of the world (1 Kings 9:26; 10:11, 26, 28; 22:48; 2 Chr.
   1:16; 9:10, 21). After Solomon's time their trade with foreign
   nations began to decline. After the Exile it again expanded into
   wider foreign relations, because now the Jews were scattered in
   many lands.


Bouvier's Law Dictionary, Revised 6th Ed (1856):

MERCHANT. One whose business it is to buy and sell merchandise; this applies
to all persons who habitually trade in merchandise. 1 Watts & S. 469; 2
Salk. 445.
     2. In another sense, it signifies a person who owns ships, and trades,
by means of them, with foreign nations, or with the different States of the
United States; these are known by the name of shipping merchants. Com. Dig.
Merchant, A; Dyer, R. 279 b; Bac. Ab. h.t.
     3. According to an old authority, there are four species of merchants,
namely, merchant adventurers, merchant dormant, merchant travellers, and
merchant residents. 2 Brownl. 99. Vide, generally, 9 Salk. R. 445; Bac. Ab.
h.t.; Com. Dig. h.t.; 1 Bl. Com. 75, 260; 1 Pard. Dr. Com. n. 78



The Devil's Dictionary (1881-1906):

MERCHANT, n.  One engaged in a commercial pursuit.  A commercial
pursuit is one in which the thing pursued is a dollar.