Word Study
sheathbill
CIDE DICTIONARY
sheathbill, n.
Either one of two species of birds composing the genus Chionis , and family Chionidæ , native of the islands of the Antarctic seas. [1913 Webster]
" They are related to the gulls and the plovers, but more nearly to the latter. The base of the bill is covered with a saddle-shaped horny sheath, and the toes are only slightly webbed. The plumage of both species is white." [1913 Webster]
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