The Collaborative International Dictionary of English v.0.48:

Coinage \Coin"age\, n. [From Coin, v. t., cf. Cuinage.]
   1. The act or process of converting metal into money.
      [1913 Webster]

            The care of the coinage was committed to the
            inferior magistrates.                 --Arbuthnot.
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   2. Coins; the aggregate coin of a time or place.
      [1913 Webster]

   3. The cost or expense of coining money.
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   4. The act or process of fabricating or inventing; formation;
      fabrication; that which is fabricated or forged.
      "Unnecessary coinage . . . of words." --Dryden.
      [1913 Webster]

            This is the very coinage of your brain. --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

coinage
    n 1: coins collectively [syn: coinage, mintage, specie,
         metal money]
    2: a newly invented word or phrase [syn: neologism, neology,
       coinage]
    3: the act of inventing a word or phrase [syn: neologism,
       neology, coinage]

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "coinage":
   and pence, artifact, authorship, beginning, brainchild,
   breakthrough, cash, child, circulating medium, coined liberty,
   coining, cold cash, composition, conception, concoction,
   contrivance, contriving, counterfeiting, creation, creative effort,
   creature, crowning achievement, currency, devising, discovery,
   distillation, dollars, effect, emergency money, end product,
   essence, extract, fabrication, filthy lucre, forgery,
   fractional currency, fruit, generation, ghost word, gold,
   handiwork, hard cash, hard currency, hatching, improvisation,
   innovation, introduction, invention, issue, leap, legal tender,
   lucre, making do, mammon, managed currency, manufacture,
   masterpiece, masterwork, medium of exchange, mintage, money,
   necessity money, neologism, neology, neoterism, new mintage,
   new phase, new sense, new word, newfangled expression, nonce word,
   novelty, offspring, opera, opus, opuscule, origination, outcome,
   outgrowth, pelf, postage currency, postal currency, pounds,
   product, production, result, scrip, shillings, silver,
   soft currency, specie, stamping, sterling, striking,
   the almighty dollar, the wherewith, the wherewithal, work