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actinium (n.)
[actinium 词源字典]
radioactive element discovered in 1899, from Greek
actin-
, comb. form of
aktis
(genitive
aktinos
) "ray, radiance" (see
actino-
) + chemical suffix
-ium
.
[actinium etymology, actinium origin, 英语词源]
[actinium 词源字典]