brain fart

An inelegant way of saying, "I forgot," it refers to your mind going blank. Someone may say, "Sorry, I just had a brain fart." It can also refer to a situation in which someone speaks "out of turn," especially to a superior. For example, if you march into your boss's office and speak your mind without first thinking about the possible consequences, you've just had a brain fart. OK, maybe it's not a technical term but it is a common expression you hear in the corridors of high-tech offices ;-)