1.Any of several large carplike North American fish.
2.(Zool.) Any of several large fresh-water fishes of the family Catostomidae (also called suckers), of the Mississippi valley. The red-mouthed or brown (Ictiobus bubalus), the big-mouthed buffalofish (Ictiobus cyrinellus, formerly called Bubalichthys urus), the black buffalofish (Ictiobus niger), and the small-mouthed buffalofish (Ictiobus bubalus, formerly called Bubalichthys altus), are among the more important species used as food.