Source : Webster's Revised Unabridged Dictionary (1913)

   Note: The common or sea lamprey of America and Europe
         ({Petromyzon marinus}), which in spring ascends rivers
         to spawn, is considered excellent food by many, and is
         sold as a market fish in some localities. The smaller
         river lampreys mostly belong to the genus
         {Ammoc[oe]les}, or {Lampetra}, as {A. fluviatilis}, of
         Europe, and {A. [ae]pypterus} of America. All lampreys
         attach themselves to other fishes, as parasites, by
         means of the suckerlike mouth.

Source : WordNet®

Petromyzon marinus
     n : large anadromous lamprey sometimes used as food; destructive
         of native fish fauna in the Great Lakes [syn: {sea
         lamprey}]