A very large oceanic fish (Xiphias gladius), the only
   representative of the family Xiphiidae. It is highly valued as a food
   fish. The bones of the upper jaw are consolidated, and form a long,
   rigid, swordlike beak; the dorsal fin is high and without distinct
   spines; the ventral fins are absent. The adult is destitute of teeth.
   It becomes sixteen feet or more long.