The Collaborative International Dictionary of English v.0.48:

Baker \Bak"er\, n. [AS. b[ae]cere. See Bake, v. t.]
   1. One whose business it is to bake bread, biscuit, etc.
      [1913 Webster]

   2. A portable oven in which baking is done. [U.S.]
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   A baker's dozen, thirteen.

   Baker foot, a distorted foot. [Obs.] --Jer. Taylor.

   Baker's itch, a rash on the back of the hand, caused by the
      irritating properties of yeast.

   Baker's salt, the subcarbonate of ammonia, sometimes used
      instead of soda, in making bread.
      [1913 Webster]