stork vs white stork

stork and white stork both are nouns.

Word	Noun	Adjective	Verb	Adverb
stork	Yes	No	No	No
white stork	Yes	No	No	No

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

stork: large mostly Old World wading birds typically having white-and-black plumage
white stork: the common stork of Europe; white with black wing feathers and a red bill

stork (noun)	white stork (noun)
large mostly Old World wading birds typically having white-and-black plumage	the common stork of Europe; white with black wing feathers and a red bill