from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A short-lived association of an electron and a positron bound together in a configuration resembling the hydrogen atom.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun physics, chemistry An exotic atom consisting of a positron and an electron, but having no nucleus
  • noun physics An onium consisting of a positron (anti-electron) and an electron, as a particle–anti-particle bound pair.


Sorry, no etymologies found.


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