The Collaborative International Dictionary of English v.0.48:

Symplectic \Sym*plec"tic\, a. [Gr. ? plaiting together, fr. ? to
   plait together.] (Anat.)
   Plaiting or joining together; -- said of a bone next above
   the quadrate in the mandibular suspensorium of many fishes,
   which unites together the other bones of the suspensorium. --
   n. The symplectic bone.
   [1913 Webster]