JACKANAPES
whippersnapper, jackanapes, lightweight
(noun) someone who is unimportant but cheeky and presumptuous
Source: WordNet® 3.1
Etymology 1
Noun
jackanapes (plural jackanapeses)
(obsolete) A monkey.
(dated, pejorative) An impudent or mischievous person.
Usage notes
Originally the singular form, jackanapes is also analyzed as a plural (due to the -s), and hence jackanape was formed as a singular backformation.
Etymology 2
Noun
jackanapes
plural of jackanape
Source: Wiktionary
Jack"a*napes, n. Etym: [For Jack o' (= of) apes; prop., a man who
exhibits apes.] [Written also jackanape.]
1. A monkey; an ape. Shak.
2. A coxcomb; an impertinent or conceited fellow.
A young upstart jackanapes. Arbuthnot.
Source: Webster’s Unabridged Dictionary 1913 Edition