The Collaborative International Dictionary of English v.0.48:

Forkbeard \Fork"beard`\, n. (Zool.)
   (a) A European fish (Raniceps raninus), having a large flat
       head; -- also called tadpole fish, and lesser forked
       beard.
   (b) The European forked hake or hake's-dame (Phycis
       blennoides); -- also called great forked beard.
       [1913 Webster]