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americium Syllabification: am·er·i·ci·um
Pronunciation: /aməˈrisēəm/ /aməˈriSHēəm/

Definition of americium in English:


The chemical element of atomic number 95, a radioactive metal of the actinide series. (Symbol: Am)

Americium does not occur naturally and was first made by bombarding plutonium with neutrons. It has been used in industrial measuring equipment as a source of gamma rays

Example sentences
  • Internal contamination with plutonium, americium, or curium can occur through a variety of routes including ingestion, inhalation, or direct contact through wounds.
  • It was the first commercial manufacturer of plutonium and americium neutron sources for oil well, logging and other applications.
  • Trace levels of plutonium and americium from nuclear weapons tests in the 1960s can be found in most homes, as can radioactive isotopes of caesium from the Chernobyl accident in 1986.


1940s: from America (where it was first made) + -ium.

Words that rhyme with americium

francium • lawrencium • copernicium

Definition of americium in:

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