overreaching
1. [ adjective ] revealing excessive self-confidence; reaching for the heights
Synonyms: vaulting
Examples:

"vaulting ambition"

Related terms: bold
Similar spelling:   overreach
  overacting
  overreaction
  overreact
  overreckoning
  overspreading
  overstretch
  over-correct
  overeager
  overactive
  overexcited
  overcrossing
  overachieve
  overactivity
  overachiever