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definitions

cathode

[kath-ohd]
|

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.

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Nearby words

  1. cathie,
  2. cathisma,
  3. cathleen,
  4. catho,
  5. cathodal,
  6. cathode dark space,
  7. cathode glow,
  8. cathode ray,
  9. cathode rays,
  10. cathode-ray tube

Origin of cathode

1825–35; < Greek káthodos a way down, equivalent to kat- cat- + hodós way
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for cathode

British Dictionary definitions for cathode

cathode

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 Formscathodal (kæˈθəʊdəl), cathodic (kæˈθɒdɪk, -ˈθəʊ-) or cathodical, adjective

Word Origin for cathode

C19: from Greek kathodos a descent, from kata- down + hodos way
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for cathode

cathode

n.

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.

Online Etymology Dictionary, © 2010 Douglas Harper
Science definitions for cathode

cathode

[kăth′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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.