MARC is a 4 letter word that starts with M.

1. \Marc\, n. [F.]
   The refuse matter which remains after the pressure of fruit,
   particularly of grapes.
   
   

2. \Marc\, n. [AS. marc; akin to G. mark, Icel. m["o]rk, perh.
   akin to E. mark a sign. [root]106, 273.] [Written also
   {mark}.]
   1. A weight of various commodities, esp. of gold and silver,
      used in different European countries. In France and
      Holland it was equal to eight ounces.
   
   2. A coin formerly current in England and Scotland, equal to
      thirteen shillings and four pence.
   
   3. A German coin and money of account. See {Mark}.