Cathode
Battery
During discharge, the positive electrode of the cell is the cathode.
During charge, the situation reverses, and the negative electrode of the cell is the cathode.
Chemistry
Electrode where electrons are gained (reduction) in redox reactions.
Electronics
In a semiconductor diode, the terminal to which positive charge carriers flow internally and into which negative charge carriers enter from the external circuit.
In electron tubes, the electrode from which electrons are emitted into the inter-electrode space.
See also: Anode, Catholyte, Electrochemistry, Electrodes, Electrolysis.
