pygidium Meaning, Definition & Usage

Py*gid"i*um noun
Etymology
NL., fr. Gr. , dim. of the rump.
Wordforms
plural Pygidia
Definitions
  1. (Zoöl.) The caudal plate of trilobites, crustacean, and certain insects. See Illust. of Limulus and Trilobite.

Webster 1913