cathode

[kath-ohd] /ˈkæθ oʊd/

noun

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

1825-35; < Greek káthodos a way down, equivalent to kat- cat- + hodós way

Examples from the web for cathode

Different materials for the anode and cathode, of course, affect this back-and-forth movement.
Pop artists borrowed images from the cathode-ray bank of imagery, which generously made interest-free loans.
The bad news is that this highly efficient system requires an expensive, platinum-based cathode.
When the zinc oxidized, it reacted with a cathode and the copper was reduced.
For one thing, his display lags behind the best two-dimensional cathode-ray tubes in its ability to resolve fine detail.
In this type of cathode, electrons are emitted after they tunnel through a potential barrier.
When such a battery is charged, lithium ions move from the cathode to the anode.
At the cathode, oxygen molecules combine with electrons and hydrogen ions to form water.
Right now, lithium ion batteries use cobalt instead of iron in the cathode.
Laptop cold-cathode backlights operate at hundreds or even thousands of volts.

British Dictionary definitions for cathode

cathode

/ˈkæθəʊd/

noun

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

Compare anode

Derived Forms

cathodal (kæˈθəʊdəl), cathodic (kæˈθɒdɪk; -ˈθəʊ-), cathodical, adjective

Word Origin

C19: from Greek kathodos a descent, from kata- down + hodos way

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.

cathode in Science

cathode

(kāth'ōd')

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.