n. (also actinoid) Chem. any of the series of 15 radioactive elements having increasing atomic numbers from actinium to lawrencium. actinide series this series of elements.
[ ACTINIUM + -IDE as in lanthanide ]
n. (also actinoid) Chem. any of the series of 15 radioactive elements having increasing atomic numbers from actinium to lawrencium. actinide series this series of elements.
[ ACTINIUM + -IDE as in lanthanide ]
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012