howl vs shout

howl and shout both are nouns.

Word	Noun	Adjective	Verb	Adverb
howl	Yes	No	Yes	No
shout	Yes	No	Yes	No

As verbs, shout is a hypernym of howl; that is, shout is a word with a broader meaning than howl:

Other hypernyms of howl include call, cry, holler, hollo, scream, shout out, squall, yell.

howl (noun)	shout (noun)
a long loud emotional utterance	a loud utterance; often in protest or opposition
a loud sustained noise resembling the cry of a hound
the long plaintive cry of a hound or a wolf

howl (verb)	shout (verb)
laugh unrestrainedly and heartily	utter in a loud voice; talk in a loud voice (usually denoting characteristic manner of speaking)
make a loud noise, as of wind, water, or vehicles	utter a sudden loud cry
emit long loud cries	utter aloud; often with surprise, horror, or joy
cry loudly, as of animals	use foul or abusive language towards