Something that makes absolutely no sense in the context of a sentence, story, TV show, book, play or movie. Alternatively, something that is incredibly out of place.
This term
originated from Cleolinda Jones' LiveJournal recaps of the television show Lost. In one of the early episodes, the characters come across a vicious polar bear
in the middle of the jungle. This animal was so out of place and
out of context that in her recap, Cleolinda referred to it as the "OMGWTFPOLARBEAR".