cathode
/ˈkæθ.oʊd/ noun
Forms cathodes kathode
- noun (electricity) An electrode, of a cell or other electrically polarized device, through which a positive current of electricity flows outwards (and thus, electrons flow inwards). It can have either a negative or a positive voltage with respect to anode of the same polarized device (depending on whether the device is a load or a source, respectively).
- noun (by extension) The electrode at which chemical reduction of cations takes place, usually resulting in the deposition of metal onto the electrode.
- noun (electronics) The electrode from which electrons are emitted into a vacuum tube or gas-filled tube.
- noun (electronics) That electrode of a semiconductor device which is connected to the n-type material of a p-n junction.
Antonyms
Etymology
From Ancient Greek κατα- (kata-, “down”) and ὁδός (hodós, “journey, way”), equivalent to Ancient Greek κάθοδος (káthodos, “way down, descent”). Coined by English polymath William Whewell in 1834 for Michael Faraday, who introduced it later that year. By surface analysis, cath- (alternative form of cata-) + -ode.
Webster’s 1913
- noun The part of a voltaic battery by which the electric current leaves substances through which it passes, or the surface at which the electric current passes out of the electrolyte; the negative pole; --opposed to anode. Faraday. Cathode ray (Phys.), a kind of ray generated at the cathode in a vacuum tube, by the electrical discharge.
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “cathode”, CC BY-SA 4.0. Details