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-onium

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Chemistry.

a suffix used in the names of complex cations: oxonium.

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Origin of -onium

Extracted from ammonium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

Medical definitions for -onium

-onium

suff.

Containing a positively charged radical:carbonium.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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