Meaning of ACTINIUM in English

ACTINIUM

[ ak'tɪnɪəm ]

■ noun the chemical element of atomic number 89, a rare radioactive metallic element of the actinide series that occurs as an impurity in uranium ores. (Symbol: Ac )

Origin

early 20th cent.: from Gk aktis , aktin- 'ray' + -ium .

Concise Oxford English vocab.      Сжатый оксфордский словарь английского языка.