overconfident

Adjective

overconfident (comparative more overconfident, superlative most overconfident)

1. Too confident.
   • The downturn triggered by putting everyday life on hold to halt the infection should, we were told, be V-shaped: a shock, but one from which we’d soon bounce back. Like many comforting predictions in the early days of this pandemic, that is beginning to look alarmingly over-confident.2020 April 9, Gaby Hinsliff, “We used to moan about normal life, now our fear is we'll never get it back”, in The Guardian
   • By propagating a "reality distortion field"—that is, mesmerizing potential employees, investors, and strategic partners so they focus on a startup's world-changing potential rather than on its real-world risks—overconfident and charismatic founders in particular are able to persuade people to...2021, Tom Eisenmann, Why Startups Fail, Crown, →ISBN, page 41

   Synonyms:

   overweening

   Antonyms:

   underconfident, unconfident

   1. (also, sometimes, via understatement) Presumptuous, cocksure, rude, and disrespectful.
      • Near-synonyms: insolent, conceited, foolhardy, cocky