yowl vs yell

yowl and yell both are nouns.

Word	Noun	Adjective	Verb	Adverb
yowl	Yes	No	Yes	No
yell	Yes	No	Yes	No

As nouns, yell is a hypernym of yowl; that is, yell is a word with a broader meaning than yowl:

Other hypernyms of yowl include call, cry, outcry, shout, vociferation.

yowl (noun)	yell (noun)
a very loud utterance (like the sound of an animal)	a loud utterance; often in protest or opposition
	a loud utterance of emotion (especially when inarticulate)

yowl (verb)	yell (verb)
utter shrieks, as of cats	utter or declare in a very loud voice
cry loudly, as of animals	utter a sudden loud cry