Americium
/ˌæm.əˈrɪs.i.əm/noun
A radioactive chemical element with atomic number 95, symbol Am.
Did you know?Americium was discovered in 1944 during the Manhattan Project and is named by analogy with europium, honoring America as europium honors Europe.
Etymological Timeline
1944
English
americium
“A proposed name for the newly discovered synthetic element 95, modeled on europium”
1945
English
americium
“The element’s name was publicly announced after wartime secrecy restrictions eased”
1946
English
americium
“The name entered scientific and public English”
1950s
English
americium
“Americium-241 became associated with industrial gauges and other practical radioactive sources”
Modern English
English
americium
“A radioactive actinide element used notably in ionization smoke detectors”