The Collaborative International Dictionary of English v.0.48:

Percolate \Per"co*late\, v. t. [imp. & p. p. Percolated; p.
   pr. & vb. n. Percolating.] [L. percolatus, p. p. of
   percolare to percolate; per through + colare to strain.]
   To cause to pass through fine interstices, as a liquor; to
   filter; to strain. --Sir M. Hale.
   [1913 Webster]