oops

Etymology

A presumably 'natural' exclamation, attested in writing since 1921. Related to or a variation of whoops (itself attested since 1933). A shortening of whoops-a-daisy, whoopsie-daisy, or oops-a-daisy, which in turn is a mispronunciation of ups-a-daisy or upsy-daisy.

intj

1. (colloquial) Acknowledging a mistake.
   Oops! I left the lid off the ketchup.
   Oops, I did it again / I played with your heart, got lost in the game 2000, Max Martin, Rami Yacoub (lyrics and music), “Oops!… I Did It Again”, in Oops!… I Did It Again, performed by Britney Spears

noun

1. A minor mistake or unforseen difficulty.
   It's an oops, but one that's your fault, not your puppy's. 2011, Housetraining, page 14
   Every plan and every activity has an “oops.” Oops, we forgot to..., oops, who was supposed to do that? We all have experienced “oopses”. 2013, Bruce Tucker, Leadership at the Crossroads
   Isn't she the same woman who works at Wings that you and Billy almost got arrested for helping her with her last little oops? 2014, Al Rennie, Clearwater Oops!
   My parents had moved to this house, which sat on the border of Corktown and Mexicantown, from their tiny apartment in Ann Arbor—once they found out that their little oops was actually two little oops. 2015, Dawn Klehr, If You Wrong Us

verb

1. (intransitive, colloquial) To make a mistake; to blunder.