waterfowl vs screamer

waterfowl and screamer both are nouns.

Word	Noun	Adjective	Verb	Adverb
waterfowl	Yes	No	No	No
screamer	Yes	No	No	No

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

waterfowl: freshwater aquatic bird
screamer: gooselike aquatic bird of South America having a harsh trumpeting call

Other hyponyms of waterfowl include anseriform bird.

waterfowl (noun)	screamer (noun)
freshwater aquatic bird	a very hard hit ball
	gooselike aquatic bird of South America having a harsh trumpeting call
	a sensational newspaper headline
	someone who communicates vocally in a very loud voice