astatine
[ as-tuh-teen, -tin ]
/ ˈæs təˌtin, -tɪn /
noun Chemistry.
a rare element of the halogen family. Symbol: At; atomic number: 85.
Nearby words
astasia, astasia-abasia, astatic, astatic galvanometer, astatide, astatine, astbury, asteatosis, aster, aster yellows, 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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Medicine 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.
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Science definitions for astatine
astatine
[ ăs′tə-tēn′ ]
At
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.
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