punch line vs laugh line

punch line and laugh line both are nouns.

Word	Noun	Adjective	Verb	Adverb
punch line	Yes	No	No	No
laugh line	Yes	No	No	No

As nouns, punch line and laugh line are synonyms defined as:

Other synonyms of punch line include gag line, tag line.

punch line (noun)	laugh line (noun)
the point of a joke or humorous story	the point of a joke or humorous story
	a wrinkle in the skin at the outer corner of your eyes