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Webster 1913 Edition

Crissum

‖

Cris′sum

(kr?s′s?m)

,,

Noun.

;

pl.

Crissa

(-s[GREEK])

.

[NL.; cf. L.

crisso

to move the haunches.]

(Zool.)

That part of a bird, or the feathers, surrounding the cloacal opening; the under tail coverts.