The Collaborative International Dictionary
Sheartail
Sheartail \Shear"tail`\, n. (Zo["o]l.)
The common tern.
Any one of several species of humming birds of the genus Thaumastura having a long forked tail.
Wiktionary
sheartail
n. 1 The common tern, ''Sterna hirundo''. 2 A hummingbird of any of several species of the genus ''Thaumastura'', having a long forked tail.