heron vs wading bird

heron and wading bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
heron	Yes	No	No	No
wading bird	Yes	No	No	No

As nouns, wading bird is a hypernym of heron; that is, wading bird is a word with a broader meaning than heron:

heron: grey or white wading bird with long neck and long legs and (usually) long bill
wading bird: any of many long-legged birds that wade in water in search of food

Other hypernyms of heron include wader.

heron (noun)	wading bird (noun)
grey or white wading bird with long neck and long legs and (usually) long bill	any of many long-legged birds that wade in water in search of food