grayback vs sandpiper

grayback and sandpiper both are nouns.

Word	Noun	Adjective	Verb	Adverb
grayback	Yes	No	No	No
sandpiper	Yes	No	No	No

As nouns, sandpiper is a hypernym of grayback; that is, sandpiper is a word with a broader meaning than grayback:

grayback: a sandpiper that breeds in the Arctic and winters in the Southern Hemisphere
sandpiper: any of numerous usually small wading birds having a slender bill and piping call; closely related to the plovers

grayback (noun)	sandpiper (noun)
a dowitcher with a grey back	any of numerous usually small wading birds having a slender bill and piping call; closely related to the plovers
a sandpiper that breeds in the Arctic and winters in the Southern Hemisphere