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Definition of
actinium noun
from the Oxford Advanced American Dictionary
actinium
noun
noun
NAmE
/
/
ækˈtɪniəm
/
/
[
uncountable
]
(
symbol
Ac
)
jump to other results
a chemical element.
Actinium
is a
radioactive
metal.
See
actinium
in the Oxford Advanced Learner's Dictionary
Check pronunciation:
actinium
Nearby words
acting
noun
acting
adjective
actinium
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action
noun
actionable
adjective