Dicionário

Rissoid

Webster's Dictionary 1913

Ris″soid (?), n. [NL. Rissoa, the typical genus (fr. A. Risso, an Italian naturalist) + -oid.] (Zoöl.) Any one of very numerous species of small spiral gastropods of the genus Rissoa, or family Rissoidæ, found both in fresh and salt water.