The Collaborative International Dictionary of English v.0.48:

Evagination \E*vag`i*na"tion\, n. [L. evaginatio an extending,
   evaginare to unsheathe; e out + vagina sheath.]
   1. The act of unsheathing.
      [1913 Webster]

   2. An outgrowth or protruded part.
      [Webster 1913 Suppl.]