Source : Webster's Revised Unabridged Dictionary (1913)

Shrinkage \Shrink"age\, n.
   1. The act of shrinking; a contraction into less bulk or
      measurement.

   2. The amount of such contraction; the bulk or dimension lost
      by shrinking, as of grain, castings, etc.

   3. Decrease in value; depreciation. [Colloq.]

Source : WordNet®

shrinkage
     n 1: process or result of becoming less or smaller; "the material
          lost 2 inches per yard in shrinkage" [syn: {shrinking}]
     2: the amount by which something shrinks
     3: the act of stealing goods that are on display in a store;
        "shrinkage is the retail trade's euphemism for
        shoplifting" [syn: {shoplifting}]