any of a family (Cetorhinidae) of plankton-eating giant sharks (order Lamniformes) with small, weak teeth: often found feeding along the surface in northern seas
See basking shark in American Heritage Dictionary 4
noun
A very large shark (Cetorhinus maximus) that measures up to about 12 meters (40 feet) in length, feeds on plankton, and often floats near the surface of water.