cath·​ode | \ ˈka-ˌthōd How to pronounce cathode (audio) \

Definition of cathode

1 : the electrode of an electrochemical cell at which reduction occurs:
a : the negative terminal of an electrolytic cell
b : the positive terminal of a galvanic cell
2 : the electron-emitting electrode of an electron tube broadly : the negative electrode of a diode — compare anode

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Other Words from cathode

cathodal \ ˈka-​ˌthō-​dᵊl How to pronounce cathodal (audio) \ adjective
cathodally adverb
cathodic \ ka-​ˈthä-​dik How to pronounce cathodic (audio) , -​ˈthō-​ How to pronounce cathodic (audio) \ adjective
cathodically \ ka-​ˈthä-​di-​k(ə-​)lē How to pronounce cathodically (audio) , -​ˈthō-​ \ adverb

Examples of cathode in a Sentence

Recent Examples on the Web

That acid, in turn, reacts on a copper catalyst coating the negative electrode, or cathode, to create CO. Robert F. Service, Science | AAAS, "This former playwright aims to turn solar and wind power into gasoline," 3 July 2019 Neuroscientists think the current makes the brain cells underneath the positive electrode (anode) work harder, while the negative electrode (cathode) has the opposite effect and calms activity in nearby neurons. The Economist, "Zapping the brain improves creativity," 14 June 2019 Early computers sported dark mode by default, in part because black and white cathode-ray-tube monitors displayed white, amber, or green text on their inky black screens. Arielle Pardes, WIRED, "Do You Really Need Dark Mode?," 8 June 2019 Applying voltage to the devices pushes positively charged silver ions out of the silver sulfide and toward the silver cathode layer, where they are reduced to metallic silver. Quanta Magazine, "A Brain Built From Atomic Switches Can Learn," 20 Sep. 2017 The hulking lithium-ion battery in the belly of a Tesla Model S stores electrical energy as a voltage across an anode and cathode. Avery Thompson, Popular Mechanics, "Where Are All the Hydrogen Cars?," 10 Aug. 2018 Heard on the Street has previously featured car-chip group Infineon and battery-cathode manufacturer Umicore as plays on electrification. Stephen Wilmot, WSJ, "The Fool’s Game of Picking the Electric Car Champ," 27 July 2018 The beautiful clock charges via USB and is remote controlled, yet displays time in a Nixie Tube—an old-fashioned cathode tube with neon filaments. John Wenz, Popular Mechanics, "This Retro Cathode Ray Tube Clock Is Powered by USB," 13 Feb. 2015 At the cathode, catalysts split N2 molecules and prompt the hydrogen ions and electrons to react with nitrogen and make ammonia. Robert F. Service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cathode.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cathode

1834, in the meaning defined at sense 1

History and Etymology for cathode

Greek kathodos way down, from kata- + hodos way

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Statistics for cathode

Last Updated

6 Jul 2019

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Time Traveler for cathode

The first known use of cathode was in 1834

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English Language Learners Definition of cathode

technical : the part of an electrical device (such as a battery) where electrons enter


cath·​ode | \ ˈkath-ˌōd How to pronounce cathode (audio) \

Medical Definition of cathode

1 : the electrode of an electrochemical cell at which reduction occurs: as
a : the negative terminal of an electrolytic cell
b : the positive terminal of a storage battery that is delivering current
2 : the electron-emitting electrode of an electron tube — compare anode

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More from Merriam-Webster on cathode

Spanish Central: Translation of cathode

Nglish: Translation of cathode for Spanish Speakers Encyclopedia article about cathode

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