'Spongia dura' definitions:

Definition of 'Spongia dura'

From: GCIDE

Hardhead \Hard"head`\ (-h[e^]d`), n.
1. Clash or collision of heads in contest. --Dryden. [1913 Webster]
2. (Zool.) (a) The menhaden. See Menhaden. [Local, U. S.] (b) Block's gurnard (Trigla gurnardus) of Europe. (c) A California salmon; the steelhead. (d) The gray whale. See Gray whale, under Gray. (e) A coarse American commercial sponge (Spongia dura). [1913 Webster] hardheaded