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

Nearby words

  1. -oma,
  2. -ome,
  3. -on,
  4. -one,
  5. -onic,
  6. -ont,
  7. -onym,
  8. -oon,
  9. -opia,
  10. -opsia

Origin of -onium

extracted from ammonium

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Medicine definitions for -onium



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.