Upstart

/ˈʌpˌstɑrt/

Synonyms

  • newcomer
  • arriviste
  • neophyte
  • parvenu
  • rising star

Slang Meanings

A show-off or someone who brags about their success.
Ever since he got that promotion, he's been acting like such an upstart.
A person who presumes to act with authority but is inexperienced.
Don't listen to him, he's just an upstart trying to sound important.