FORKTAIL

Etymology

Noun

forktail (plural forktails)

Any of various small insectivorous birds in the genus Enicurus.

(UK, dialect) A salmon in its fourth year's growth.

Source: Wiktionary

Fork"tail`, n. (Zoöl.) (a) One of several Asiatic and East Indian passerine birds, belonging to Enucurus, and allied genera. The tail is deeply forking. (b) A salmon in its fourth year's growth. [Prov. Eng.]

Source: Webster’s Unabridged Dictionary 1913 Edition