Oops/ʊps/ Definition 1 of 2Pro Tip 1/3Minor Mistake Say 'oops' when you do something slightly wrong, but it's not a big problem. Oops, I forgot to close the door! Pro Tip 2/3Informality 'Oops' is casual and typically used in informal or friendly settings, not formal ones. Oops, spilled a bit of coffee on the table! Pro Tip 3/3Immediate Reaction Use 'oops' right after a small accident happens to acknowledge it. Oops, I accidentally dropped your pen.