Definitions
1.nounAn electrode, of a cell or other electrically polarized device, through which a positive current of electricity flows outwards (and thus, electrons flow inwards). It usually, but not always, has a positive voltage.
2.noun(by extension) The electrode at which chemical reduction of cations takes place, usually resulting in the deposition of metal onto the electrode.
3.nounThe electrode from which electrons are emitted into a vacuum tube or gas-filled tube.
4.nounThat electrode of a semiconductor device which is connected to the n-type material of a p-n junction.