noun Shortened form of "wall vampire" which is a slang for a wall adaptor (AC or DC) as they are always on, regardless of whether a device is being powered by them (energy is lost through the transformer core, as well as heat produced). As such, they drain the power like a vampire, and as they are on the wall, they are aptly named 'wall vamps'. It can also be used to refer to chargers which take power in excess while idle.
Gah, his phone charger is such a wall vamp.
by Vasily K. July 20, 2006