'Hairtail' definitions:

Definition of 'hairtail'

From: WordNet
noun
Long-bodied marine fishes having a long whiplike scaleless body and sharp teeth; closely related to snake mackerel [syn: cutlassfish, frost fish, hairtail]

Definition of 'Hairtail'

From: GCIDE
  • Hairtail \Hair"tail`\ (-t[=a]l`), n. (Zool.) Any species of marine fishes of the genus Trichiurus; esp., Trichiurus lepturus of Europe and America. They are long and like a band, with a slender, pointed tail. Called also bladefish. [1913 Webster]