little grebe vs grebe

little grebe and grebe both are nouns.

Word	Noun	Adjective	Verb	Adverb
little grebe	Yes	No	No	No
grebe	Yes	No	No	No

As nouns, grebe is a hypernym of little grebe; that is, grebe is a word with a broader meaning than little grebe:

little grebe: small European grebe
grebe: small compact-bodied almost completely aquatic bird that builds floating nests; similar to loons but smaller and with lobate rather than webbed feet

little grebe (noun)	grebe (noun)
small European grebe	small compact-bodied almost completely aquatic bird that builds floating nests; similar to loons but smaller and with lobate rather than webbed feet