eyas
Concise Oxford English Dictionary © 2008 Oxford University Press:
eyas /ˈʌɪəs/
▶noun (pl. eyasses) a young hawk, especially (in falconry) an unfledged nestling taken from the nest for training.
– origin C15 (orig. nyas): from Fr. niais, based on L. nidus ‘nest’; the initial n was lost by wrong division of a nyas; cf. adder1.
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