actinium

noun

ac·tin·i·um | \ ak-ˈti-nē-əm

Definition of actinium

: a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende — see Chemical Elements Table

Examples of actinium in a Sentence

Recent Examples on the Web Other theorists have predicted that hydrides such as calcium hydride or actinium hydride should superconduct at close to room temperature—and at a pressure considerably less than that needed for CSH. — Robert F. Service, Science | AAAS, 26 Aug. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'actinium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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Actinistia

actinium

actinium emanation

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Last Updated

8 Sep 2021

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“Actinium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/actinium. Accessed 20 Sep. 2021.

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More Definitions for actinium

actinium

noun

ac·tin·i·um | \ ak-ˈtin-ē-əm

Medical Definition of actinium

: a radioactive trivalent metallic element that resembles lanthanum in chemical properties and that is found especially in pitchblende —symbol Ac — see Chemical Elements Table