cation

noun

cat·​ion ˈkat-ˌī-ən How to pronounce cation (audio)
ˈka-(ˌ)tī-ən
: the ion in an electrolyzed solution that migrates to the cathode
broadly : a positively charged ion

Word History

Etymology

Greek kation, neuter of katiōn, present participle of katienai to go down, from kata- cata- + ienai to go — more at issue entry 1

First Known Use

1834, in the meaning defined above

Time Traveler
The first known use of cation was in 1834

Rhymes for cation

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Browse Nearby Words

catinga
cation
cation-active
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Cite this Entry

“Cation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cation. Accessed 29 Oct. 2025.

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Kids Definition

cation

noun
cat·​ion ˈkat-ˌī-ən How to pronounce cation (audio)
: the ion in solution during electrolysis that travels to the cathode
also : a positively charged ion

Medical Definition

cation

noun
cat·​ion ˈkat-ˌī-ən How to pronounce cation (audio)
: the ion in an electrolyzed solution that migrates to the cathode
broadly : a positively charged ion
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