The Collaborative International Dictionary of English v.0.48:

Jib \Jib\, v. t. & i. [imp. & p. p. Jibbed; p. pr. & vb. n.
   Jibbing.] Also Jibb \Jibb\ [Cf. Jib a sail, Gybe.]
   (Chiefly Naut.)
   To shift, or swing round, as a sail, boom, yard, etc., as in
   tacking.
   [Webster 1913 Suppl.]