1. (noun) torrentfish, Cheimarrichthys fosteri - a smallish, stocky fish with a strongly arched back and flattened ventral surface, large eyes on top of a head shaped like an inverted shovel, the mouth below , and the lower jaw distinctly shorter than the upper. An endemic fish found in larger, braided, gravel, open rivers of the North and South Islands. Solitary and secretive.