The Collaborative International Dictionary of English v.0.48:

Inflation \In*fla"tion\, n. [L. inflatio: cf. F. inflation.]
   1. The act or process of inflating, or the state of being
      inflated, as with air or gas; distention; expansion;
      enlargement. --Boyle.
      [1913 Webster]

   2. The state of being puffed up, as with pride; conceit;
      vanity. --B. Jonson.
      [1913 Webster]

   3. Persistent expansion or increase in the general level of
      prices, usually caused by overissue of currency, and
      resulting in a reduced value of the currency. It is
      contrasted with deflation, and is when it occurs to a
      very high degree is called hyperinflation. [U.S.]
      [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

inflation
    n 1: a general and progressive increase in prices; "in inflation
         everything gets more valuable except money" [syn:
         inflation, rising prices] [ant: deflation,
         disinflation]
    2: (cosmology) a brief exponential expansion of the universe
       (faster than the speed of light) postulated to have occurred
       shortly after the big bang
    3: lack of elegance as a consequence of being pompous and puffed
       up with vanity [syn: ostentation, ostentatiousness,
       pomposity, pompousness, pretentiousness, puffiness,
       splashiness, inflation]
    4: the act of filling something with air [ant: deflation]