name given to various dark-coloured fishes, including the tautog (see wrasse), bowfin, Alaska blackfish (qq.v.), and black sea bass (see sea bass). Also known as blackfish are the pilot whale (q.v.), a mammal; Orthodon microlepidotus, a California minnow; the black ruff (Centrolophus niger), a European deep-sea rudderfish; and several Australian food fishes.