onium

  1. Noun.  (chemistry) any cation derived by the addition of a proton to the hydride of any element of the nitrogen, chalcogen or halogen families.
  2. Noun.  (chemistry) any organic derivative of these compounds.
  3. Noun.  (physics) the bound pair of a particle and its antiparticle.

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This entry was last updated on RefTopia from its source on 3/20/2012.