water ouzel vs dipper

water ouzel and dipper both are nouns.

Word	Noun	Adjective	Verb	Adverb
water ouzel	Yes	No	No	No
dipper	Yes	No	No	No

As nouns, water ouzel and dipper are synonyms defined as:

water ouzel and dipper: small stocky diving bird without webbed feet; frequents fast-flowing streams and feeds along the bottom

water ouzel (noun)	dipper (noun)
small stocky diving bird without webbed feet; frequents fast-flowing streams and feeds along the bottom	small North American diving duck; males have bushy head plumage
	small stocky diving bird without webbed feet; frequents fast-flowing streams and feeds along the bottom
	a ladle that has a cup with a long handle