sight gag vs visual joke

sight gag and visual joke both are nouns.

Word	Noun	Adjective	Verb	Adverb
sight gag	Yes	No	No	No
visual joke	Yes	No	No	No

As nouns, sight gag and visual joke are synonyms defined as:

sight gag and visual joke: a joke whose effect is achieved by visual means rather than by speech (as in a movie)

sight gag (noun)	visual joke (noun)
a joke whose effect is achieved by visual means rather than by speech (as in a movie)	a joke whose effect is achieved by visual means rather than by speech (as in a movie)