<ornithology> The common tern. Any one of several species of humming birds of the genus Thaumastura having a long forked tail. ... (06 Mar 1998) ... Found on http://www.encyclo.co.uk/local/20973
Shear'tail` noun (Zoology) (a) The common tern. (b) Any one of several species of humming birds of the genus Thaumastura having a long forked tail. Found on http://www.encyclo.co.uk/webster/S/84