curlew vs Eskimo curlew

curlew and Eskimo curlew both are nouns.

Word	Noun	Adjective	Verb	Adverb
curlew	Yes	No	No	No
Eskimo curlew	Yes	No	No	No

As nouns, Eskimo curlew is a hyponym of curlew; that is, Eskimo curlew is a word with a more specific, narrower meaning than curlew:

curlew: large migratory shorebirds of the sandpiper family; closely related to woodcocks but having a down-curved bill
Eskimo curlew: New World curlew that breeds in northern North America

Other hyponyms of curlew include European curlew, Numenius arquata, Numenius borealis.

curlew (noun)	Eskimo curlew (noun)
large migratory shorebirds of the sandpiper family; closely related to woodcocks but having a down-curved bill	New World curlew that breeds in northern North America