clown vs jester

clown and jester both are nouns.

Word	Noun	Adjective	Verb	Adverb
clown	Yes	No	Yes	No
jester	Yes	No	No	No

As nouns, jester is a hyponym of clown; that is, jester is a word with a more specific, narrower meaning than clown:

clown: a person who amuses others by ridiculous behavior
jester: a professional clown employed to entertain a king or nobleman in the Middle Ages

Other hyponyms of clown include harlequin, fool, motley fool, whiteface, zany.

clown (noun)	jester (noun)
a person who amuses others by ridiculous behavior	a professional clown employed to entertain a king or nobleman in the Middle Ages
a rude or vulgar fool

clown (verb)	jester (verb)
act as or like a clown