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Webster 1913 Edition

Rissoid

Ris′soid

,

Noun.

[NL.

Rissoa

, the typical genus ( fr. A.

Risso

, an Italian naturalist) +

-oid

.]

(Zool.)

Any one of very numerous species of small spiral gastropods of the genus

Rissoa

, or family

Rissoidae

, found both in fresh and salt water.