cathode

noun

cath·​ode ˈka-ˌthōd How to pronounce cathode (audio)
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
cathodal
ˈka-ˌthō-dᵊl How to pronounce cathode (audio)
adjective
cathodally adverb
cathodic
ka-ˈthä-dik How to pronounce cathode (audio) -ˈthō- How to pronounce cathode (audio)
adjective
cathodically
ka-ˈthä-di-k(ə-)lē How to pronounce cathode (audio)
-ˈthō-
adverb

Examples of cathode in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The researchers built the cathode from lead-halide perovskites, a semiconductor material that absorbs light and converts it into electrical energy. — New Atlas, 24 Oct. 2026 In time, this could help scientists design sodium-ion cathodes optimized for specific needs, such as higher energy storage, faster charging, or longer-lasting performance. — Muskan Bhatia, Interesting Engineering, 22 Oct. 2026 The deadline The first thing out of that loop is DRX, short for disordered rocksalt, a family of cathode materials that use neither nickel nor cobalt. — Nick Lichtenberg, Fortune, 15 Oct. 2026 See All Example Sentences for cathode

Word History

Etymology

Greek kathodos way down, from kata- + hodos way

First Known Use

1834, in the meaning defined at sense 1

Time Traveler
The first known use of cathode was in 1834

Phrases Containing cathode

Rhymes for cathode

See All Rhymes for cathode

Browse Nearby Words

cathisma
cathode
cathode current
See all Nearby Words

Cite this Entry

“Cathode.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cathode. Accessed 27 Oct. 2026.

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Kids Definition

cathode

noun
cath·​ode ˈkath-ˌōd How to pronounce cathode (audio)
1
: the negative electrode of an electrolytic cell compare anode sense 1
2
: the positive terminal of a battery
3
: the electron-emitting electrode of an electron tube
cathodic
ka-ˈthäd-ik How to pronounce cathode (audio)
adjective

Medical Definition

cathode

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

More from Merriam-Webster on cathode

Britannica.com: Encyclopedia article about cathode

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