1. [very common] To fail. A program loses
when it encounters an exceptional condition or fails to work in the
expected manner. 2. To be exceptionally unesthetic or crocky.
3. Of people, to be obnoxious or unusually stupid (as opposed to
ignorant). See also deserves to lose. 4. n. Refers to
something that is losing, especially in the phrases "That's a
lose!" and "What a lose!"