Definition of americium
: a radioactive metallic element produced artificially by bombarding plutonium with high-energy neutrons — see element table
Recent Examples of americium from the Web
The criminal complaint says those were thorium and americium, both radioactive metals.
Power would come from a tiny radioactive source like americium, the element in smoke detectors.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'americium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of americium
New Latin, from America + New Latin -ium
First Known Use: 1946See Words from the same year
Learn More about americium
Britannica.com: Encyclopedia article about americium
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