Cathode, (from the Greek kathodes — a way down, a return; the term was proposed by the English physicist M. Faraday in 1834),
1) the negative electrode of a vacuum-tube or gas-discharge device, serving as the source of the electrons that provide the conductivity of the interelectrode space in a vacuum or in a gas. According to the mechanism by which the electrons are emitted, a distinction is drawn between thermionic cathodes, photocathodes and cold cathodes.
2) The negative electrode of a current source (a galvanic cell, a storage battery and others).
3) The electrode of an electrolytic bath, an electric arc or other similar devices that is connected to the negative pole of the current source.
1) the negative electrode of a vacuum-tube or gas-discharge device, serving as the source of the electrons that provide the conductivity of the interelectrode space in a vacuum or in a gas. According to the mechanism by which the electrons are emitted, a distinction is drawn between thermionic cathodes, photocathodes and cold cathodes.
2) The negative electrode of a current source (a galvanic cell, a storage battery and others).
3) The electrode of an electrolytic bath, an electric arc or other similar devices that is connected to the negative pole of the current source.