- in an electroplating cell, the negatively charged electrode, from which current flows
- in an electron tube, the negatively charged electron emitter
- in a battery that is a source of electric current, as a dry cell or storage battery, the positive electrode which receives the electrons from the external circuit
Origin of cathodecoined by Faraday from Classical Greek kathodos, descent from kata-, down + -ode
- A negatively charged electrode, as of an electrolytic cell, storage battery, diode, or electron tube.
- The positively charged terminal of a primary cell or a storage battery that is supplying current.
Origin of cathodeGreek kathodos descent kat-, kata- cata- hodos way, path
- (electricity) An electrode, of a cell or other electrically polarized device, through which a current of electricity flows inwards (thus, electrons flow outwards). It usually, but not always, has a negative voltage.
- (chemistry, by extension) The electrode at which chemical reduction of cations takes place, usually resulting in the deposition of metal onto the electrode.
- (electronics) The electrode from which electrons are emitted into a vacuum tube or gas-filled tube.
- (electronics) That electrode of a semiconductor device which is connected to the n-type material of a p-n junction.
From Ancient Greek κάθοδος (kathodos, “descent, way down”).
cathode - Computer Definition
The terminal on a device that emits current. In the cathode ray tubes (CRT) of the bulky TVs and monitors prior to flat panels, the negative cathode emits electrons that are attracted to the positive "anode." Current flows out of cathodes and into anodes. Depending on the application, a cathode may be considered positive or negative. Derived from Greek, cathode and anode mean "down" and "up" respectively. See electrode and cold cathode.