overconfident

Etymology

over- + confident

adj

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. 2020-04-09, Gaby Hinsliff, “We used to moan about normal life, now our fear is we'll never get it back”, in The Guardian
2. Presumptuous, cocksure, rude and disrespectful.