-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
Words nearby -onium
onionskin, onion snow, onion weed, Onitsha, on its merits, -onium, onium compound, Onkelos, on key, onkus, onlap
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022
How to use -onium in a sentence
This is a situation which agrees with no other city in all Egypt, except that which was the Onium of the later Jews.
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.