astatine

[ as-tuh-teen, -tin ]

/ ˈæs təˌtin, -tɪn /

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noun Chemistry.

a rare element of the halogen family. Symbol: At; atomic number: 85.

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Origin of astatine

1945–50; <Greek ástat(os) not steadfast, unstable (see astatic) + -ine²

Words nearby astatine

astasia, astasia-abasia, astatic, astatic galvanometer, astatide, astatine, Astbury, asteatosis, step in the right direction, a, aster, asteraceous

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British Dictionary definitions for astatine

astatine

/ (ˈæstəˌtiːn, -tɪn) /

noun

a radioactive element of the halogen series: a decay product of uranium and thorium that occurs naturally in minute amounts and is artificially produced by bombarding bismuth with alpha particles. Symbol: At; atomic no: 85; half-life of most stable isotope, 210 At: 8.1 hours; probable valency: 1,3,5, or 7; melting pt: 302°C; boiling pt: 337°C (est)

Word Origin for astatine

C20: from Greek astatos unstable (see astatic) + -ine ²

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Medical definitions for astatine

astatine

[ ăs′tə-tēn′, -tĭn ]

n. Symbol At

A radioactive halogen element. Its longest lived isotope has a mass number of 210 and a half-life of 8.1 hours. Atomic number 85.

Scientific definitions for astatine

astatine

[ ăs′tə-tēn′ ]

A highly unstable, rare, radioactive element that is the heaviest of the halogen elements. Its most stable isotope has a half-life of 8.3 hours. Atomic number 85; melting point 302°C; boiling point 337°C; valence probably 1, 3, 5, 7. See Periodic Table.