n. pl. nil·gais or nilgai
A large brown or bluish-gray antelope (Boselaphus tragocamelus) native to India, Nepal, and Pakistan, the male of which has short, sturdy horns and strands of long hair hanging down from the throat.
[Hindi nīlgāī, feminine of nīlgāw : nīl, dark blue (from Sanskrit nīla-) + gāw, ox, cow (from Sanskrit gauḥ; see gwou- in the Appendix of Indo-European roots).]
(click for a larger image)nilgai
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