The Collaborative International Dictionary of English v.0.48:

Oppilate \Op"pi*late\, v. t. [imp. & p. p. Oppilated; p. pr. &
   vb. n. Oppilating.] [L. oppilatus, p. p. of oppilare to
   stop up; ob (see Ob-) + pilare to ram down, to thrust.]
   To crowd together; to fill with obstructions; to block up.
   [Obs.] --Cockeram.
   [1913 Webster]