The Collaborative International Dictionary of English v.0.48:

Abnegate \Ab"ne*gate\, v. t. [imp. & p. p. Abnegated; p. pr. &
   vb. n. Abnegating.] [L. abnegatus, p. p. of abnegare; ab +
   negare to deny. See Deny.]
   To deny and reject; to abjure. --Sir E. Sandys. Farrar.
   [1913 Webster]