Whippersnapper or `whipper snapper` is a young, impertinent person. It may also refer to: ...
[n] - someone who is unimportant but cheeky and presumptuous
• (n.) A diminutive, insignificant, or presumptuous person.
jackanapes noun someone who is unimportant but cheeky and presumptuous
Whip'per·snap`per noun A diminutive, insignificant, or presumptuous person. [ Colloq.] 'Little whippersnappers like you.' T. Hughes.