laugh loudly vs laugh

laugh loudly is not a noun while laugh is a noun.

Word	Noun	Adjective	Verb	Adverb
laugh loudly	No	No	Yes	No
laugh	Yes	No	Yes	No

As verbs, laugh is a hypernym of laugh loudly; that is, laugh is a word with a broader meaning than laugh loudly:

Other hypernyms of laugh loudly include express joy, express mirth.

laugh loudly (noun)	laugh (noun)
	the sound of laughing
	a humorous anecdote or remark intended to provoke laughter
	a facial expression characteristic of a person laughing

laugh loudly (verb)	laugh (verb)
laugh boisterously	produce laughter