Shad

Any one of several species of food fishes of the Herring family. The American species (Clupea sapidissima), which is abundant on the Atlantic coast and ascends the larger rivers in spring to spawn, is an important market fish. The European allice shad, or alose (C. alosa), and the twaite shad. (C. finta), are less important species.

herring-like food fishes that migrate from the sea to fresh water to spawn

bony flesh of herring-like fish usually caught during their migration to fresh water for spawning; especially of Atlantic coast