The Collaborative International Dictionary
Shad \Shad\ (sh[a^]d), n. sing. & pl. [AS. sceadda a kind of fish, akin to Prov. G. schade; cf. Ir. & Gael. sgadan a herring, W. ysgadan herrings; all perhaps akin to E. skate a fish.] (Zo["o]l.) Any one of several species of food fishes of the Herring family. The American species ( Alosa sapidissima formerly 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 ( Alosa alosa formerly Clupea alosa), and the twaite shad ( Alosa finta formerly Clupea finta), are less important species. [Written also chad.]
Hardboaded shad, or Yellow-tailed shad, the menhaden.
Hickory shad, or Tailor shad, the mattowacca.
Long-boned shad, one of several species of important food fishes of the Bermudas and the West Indies, of the genus Gerres.
Shad bush (Bot.), a name given to the North American shrubs or small trees of the rosaceous genus Amelanchier ( A. Canadensis, and A. alnifolia) Their white racemose blossoms open in April or May, when the shad appear, and the edible berries (pomes) ripen in June or July, whence they are called Juneberries. The plant is also called service tree, and Juneberry.
Shad frog, an American spotted frog ( Rana halecina); -- so called because it usually appears at the time when the shad begin to run in the rivers.
Trout shad, the squeteague.
White shad, the common shad.