cathode (redirected from cathodal)

cathode, electrode through which current leaves an electric device. In electrolysis, it is the negative electrode in the electrolytic cell.

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cathode

Terminal or electrode at which electrons enter a system, such as an electrolytic cell or an electron tube. In a battery or other source of direct current, the cathode is the positive terminal. In a passive load it is the negative terminal. In an electron tube, such as a cathode-ray tube, electrons stream off the cathode and travel through the tube toward the anode.

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cathode

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.

Cathode Emitters

In vacuum tubes, the cathodes are the emitters, and the anodes are the collectors.

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cathode

1. the negative electrode in an electrolytic cell; the electrode by which electrons enter a device from an external circuit

2. the negatively charged electron source in an electronic valve

3. the positive terminal of a primary cell