1. Also called: reef whitetip shark a smooth dogfish, Triaenodon obseus, having white-tipped dorsal and caudal fins and occurring inshore among the reefs in the Pacific and Indian oceans and the Red Sea
2. Also called: oceanic whitetip shark a large, predominantly tropical deepwater shark, Carcharhinus longimanus, inhabiting Atlantic and Pacific waters: considered to be the most dangerous of all sharks