- the electrode or terminal by which current leaves an electrolytic cell, voltaic cell, battery, etc.
- the positive terminal of a voltaic cell or battery.
- the negative terminal, electrode, or element of an electron tube or electrolytic cell.
Origin of cathode
Examples from the Web for cathode
The cathode is preferably formed of the same metal which is to be obtained.
To the anode he attached one of the negatives, to the cathode a small piece of iron.
Waving away that orange gas, he reached for the cathode and held it up.
The cathode as shown in Fig. 41 is rather smaller than is advantageous.
The phenomenon is particularly marked at the edges and corners of the cathode.
- the negative electrode in an electrolytic cell; the electrode by which electrons enter a device from an external circuit
- the negatively charged electron source in an electronic valve
- the positive terminal of a primary cell
Word Origin and History for cathode
1834, from Latinized form of Greek kathodos "a way down," from kata- "down" (see cata-) + hodos "way" (see cede). Proposed by the Rev. William Whewell (1794-1866), English polymath, and published by English chemist and physicist Michael Faraday (1791-1867). So called from the path the electric current was supposed to take. Related: Cathodic; cathodal. Cathode ray first attested 1880, but the phenomenon known from 1859; cathode ray tube is from 1905.
- The negative electrode in an electrolytic cell, toward which positively charged particles are attracted. The cathode has a negative charge because it is connected to the negatively charged end of an external power supply.
- The source of electrons in an electrical device, such as a vacuum tube or diode.
- The positive electrode of a voltaic cell, such as a battery. The cathode gets its positive charge from the chemical reaction that happens inside the battery, not from an external source. Compare anode.