Noun
A monkey; an ape.
A coxcomb; an impertinent or conceited fellow.
Source: Webster's dictionaryCritics? Don't talk to me of critics! You think some jackanapes journalist, his soul eaten away by the maggots of jealousy and failure, has anything worthwhile to say of art? I don't. Jonathan Raban
A whoreson jackanapes must take me up for swearing as if I borrowed mine oaths of him and might not spend them at my pleasure. When a gentleman is disposed to swear, it is not for any standers-by to curtail his oaths, ha. William Shakespeare
Jackanapes went on to become the Joker's most loyal henchmen. Source: Internet