howler vs belly laugh

howler and belly laugh both are nouns.

Word	Noun	Adjective	Verb	Adverb
howler	Yes	No	No	No
belly laugh	Yes	No	No	No

As nouns, howler and belly laugh are synonyms defined as:

Other synonyms of howler include riot, scream, sidesplitter, thigh-slapper, wow.

howler (noun)	belly laugh (noun)
a glaring blunder	a joke that seems extremely funny
monkey of tropical South American forests having a loud howling cry	a burst of deep loud hearty laughter
a joke that seems extremely funny