Noun: An instance where you check something on Wikipedia, and get lost in clicking on other links. Usually it lasts for an hour, but can go all day. A very good way to soak your brain with useless, random knowledge.
I wanted to see where Duran Duran was from, and then I read the page on platinum, Cheerios, space food, Nelson Mandela, black holes, the gold standard, and human physical attractiveness. It was one hell of a wikibender.