astatine

noun

as·​ta·​tine ˈa-stə-ˌtēn How to pronounce astatine (audio)
: a radioactive halogen element discovered by bombarding bismuth with alpha particles and also formed by radioactive decay see Chemical Elements Table

Word History

Etymology

Greek astatos unsteady, from a- + statos standing, from histanai to cause to stand — more at stand

First Known Use

1947, in the meaning defined above

Time Traveler
The first known use of astatine was in 1947

Dictionary Entries Near astatine

astatic pair

astatine

astatize

See More Nearby Entries 

Cite this Entry

“Astatine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/astatine. Accessed 26 Nov. 2024.

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Kids Definition

astatine

noun
as·​ta·​tine ˈas-tə-ˌtēn How to pronounce astatine (audio)
: a radioactive element discovered by bombarding bismuth with helium nuclei see element

Medical Definition

astatine

noun
as·​ta·​tine ˈas-tə-ˌtēn How to pronounce astatine (audio)
: a radioactive halogen element discovered by bombarding bismuth with helium nuclei and also formed by radioactive decay
—symbol At

called also ekaiodine

see Chemical Elements Table

More from Merriam-Webster on astatine

Britannica.com: Encyclopedia article about astatine

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