The Collaborative International Dictionary of English v.0.48:

Butter \But"ter\, v. t. [imp. & p. p. Buttered (?); p. pr. &
   vb. n. Buttering.]
   1. To cover or spread with butter.
      [1913 Webster]

            I know what's what. I know on which side
            My bread is buttered.                 --Ford.
      [1913 Webster]

   2. To increase, as stakes, at every throw or every game.
      [Cant] --Johnson.
      [1913 Webster]