coun·​ter·​ion ˈkau̇n-tər-ˌī-ən How to pronounce counterion (audio)
: an ion having a charge opposite to that of the substance with which it is associated

Word History

First Known Use

1940, in the meaning defined above

Time Traveler
The first known use of counterion was in 1940

Dictionary Entries Near counterion

Cite this Entry

“Counterion.” Dictionary, Merriam-Webster, Accessed 29 May. 2024.

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