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Webster 1913 Edition

Pygidium

‖

Py-gid′i-um

,

Noun.

;

pl.

Pygidia

(#)

.

[NL., fr. Gr. [GREEK], dim. of [GREEK] the rump.]

(Zool.)

The caudal plate of trilobites, crustacean, and certain insects. See Illust. of

and

.