narwhal

noun1

1. •
   An Arctic toothed whale (Monodon monoceros) that grows to about 20 feet (6 meters) long, the male having a single horn-like tusk, a twisted, pointed cuspid that projects forward.

   • Moreover, both narwhals and bowheads can occur in late summer in southern Prince Regent Inlet (coming from Lancaster Sound) and may reach Fury and Hecla Strait and northern Foxe Basin. — 1986