The Collaborative International Dictionary of English v.0.48:

Coiner \Coin"er\, n.
   1. One who makes or stamps coin; a maker of money; --
      usually, a maker of counterfeit money.
      [1913 Webster]

            Precautions such as are employed by coiners and
            receivers of stolen goods.            --Macaulay.
      [1913 Webster]

   2. An inventor or maker, as of words. --Camden.
      [1913 Webster]

WordNet (r) 3.0 (2006):

coiner
    n 1: a maker of counterfeit coins
    2: someone who is a source of new words or new expressions
    3: a skilled worker who coins or stamps money [syn: coiner,
       minter, moneyer]