to express annoyance
. The phrase was made famous by Winnie-the-Pooh
The wonderful thing about "Oh, bother!" is that you can only use it effectively in situations that are mildly annoying or inconvenient. The phrase is too incongruent in situations of real distress. For example, you are working on your car and drop your tool which then rolls under the car. The correct phrase would be "Oh, bother!" If you are working on your car and it rolls over your foot on the way down the driveway and into traffic, you probably want to go with a stronger exclamation.