zany vs merry andrew

zany and merry andrew both are nouns.

Word	Noun	Adjective	Verb	Adverb
zany	Yes	Yes	No	No
merry andrew	Yes	No	No	No

As nouns, merry andrew is a hypernym of zany; that is, merry andrew is a word with a broader meaning than zany:

zany: a buffoon in one of the old comedies; imitates others for ludicrous effect
merry andrew: a person who amuses others by ridiculous behavior

Other hypernyms of zany include buffoon, clown, goof, goofball.

zany (noun)	merry andrew (noun)
a buffoon in one of the old comedies; imitates others for ludicrous effect	a person who amuses others by ridiculous behavior
a man who is a stupid incompetent fool

zany (adjective)	merry andrew (adjective)
ludicrous, foolish
like a clown