laugh at vs guy

laugh at is not a noun while guy is a noun.

Word	Noun	Adjective	Verb	Adverb
laugh at	No	No	Yes	No
guy	Yes	No	Yes	No

As verbs, laugh at and guy are synonyms defined as:

Other synonyms of laugh at include blackguard, jest at, make fun, poke fun, rib, ridicule, roast.

laugh at (noun)	guy (noun)
	a cable, wire, or rope that is used to brace something (especially a tent)
	an informal term for a youth or man

laugh at (verb)	guy (verb)
subject to laughter or ridicule	steady or support with a guy wire or cable
	subject to laughter or ridicule