Source : Webster's Revised Unabridged Dictionary (1913)

Billfish \Bill"fish`\, n. (Zo["o]l.)
   A name applied to several distinct fishes:
   (a) The garfish ({Tylosurus, or Belone, longirostris}) and
       allied species.
   (b) The saury, a slender fish of the Atlantic coast
       ({Scomberesox saurus}).
   (c) The {Tetrapturus albidus}, a large oceanic species
       related to the swordfish; the spearfish.
   (d) The American fresh-water garpike ({Lepidosteus osseus}).