Dreissena
Pronunciation : Dreis"se*na
Part of Speech : n.
Etymology : [NL. Named after Dreyssen, a Belgian physician.] (Zo?l.)
Definition : Defn: A genus of bivalve shells of which one species (D. polymorpha) is often so abundant as to be very troublesome in the fresh waters of Europe.
Source : Webster's Unabridged Dictionary, 1913