C16: variant of Jakken-apes, literally: Jack of the ape, nickname of William de la Pole (1396–1450), first Dukeof Suffolk, whose badge showed an ape's ball and chain
jackanapes in American English
(ˈdʒækəˌneɪps)
noun
1. Archaic
a monkey
2.
a conceited, insolent, presumptuous fellow
3.
a pert, mischievous child
Word origin
ME Jac Napes, nickname of William de la Pole, Duke of Suffolk (1396-1450), whose badge was a clogand a chain like a tame ape's