[sheath.bill] n (ca. 1781): either of two white shore birds (Chionis alba and C. minor of the family Chionididae) of colder parts of the southern hemisphere that have a horny sheath over the base of the upper mandible and suggest the pigeons in general appearance
SHEATHBILL
Meaning of SHEATHBILL in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012