thoric

thorium

[thawr-ee-uhm, thohr-]
noun Chemistry.
a grayish-white, lustrous, somewhat ductile and malleable, radioactive metallic element present in monazite: used as a source of nuclear energy, as a coating on sun-lamp and vacuum-tube filament coatings, and in alloys. Symbol: Th; atomic weight: 232.038; atomic number: 90; specific gravity: 11.7.
Compare thoria.


Origin:
< Neo-Latin (1829); see Thor, -ium

thoric [thawr-ik, thor-] , adjective
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World English Dictionary
thorium (ˈθɔːrɪəm)
 
n
a soft ductile silvery-white metallic element. It is radioactive and occurs in thorite and monazite: used in gas mantles, magnesium alloys, electronic equipment, and as a nuclear power source. Symbol: Th; atomic no: 90; atomic wt: 232.0381; half-life of most stable isotope, 232Th: 1.41 × 1010 years; valency: 4; relative density: 11.72; melting pt: 1755°C; boiling pt: 4788°C
 
[C19: New Latin, from Thor + -ium]
 
'thoric
 
adj

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Etymonline
Word Origin & History

thorium
rare metallic element, 1832, from Mod.L., named 1828-9 by its discoverer, Swed. chemist Jöns Jakob Berzelius (1779-1848) in honor of the Scand. god Thor (q.v.).
Online Etymology Dictionary, © 2010 Douglas Harper
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American Heritage
Medical Dictionary

thorium tho·ri·um (thôr'ē-əm)
n.
Symbol Th
A radioactive metallic element that is used in magnesium alloys; its longest-lived isotope, Th 232, has a half-life of 1.41 × 1010 years. Atomic number 90; atomic weight 232.038; approximate melting point 1,750°C; approximate boiling point 4,800°C; approximate specific gravity 11.7; valence 4.

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American Heritage
Science Dictionary
thorium   (thôr'ē-əm)  Pronunciation Key 
Symbol Th
A silvery-white, radioactive metallic element of the actinide series. It is used for fuel in some nuclear reactors and for improving the high-temperature strength of magnesium alloys. The only naturally occurring isotope of thorium, Th 232, is also its most stable, having a half-life of 14.1 billion years. Atomic number 90; atomic weight 232.038; approximate melting point 1,750°C; approximate boiling point 4,500°C; approximate specific gravity 11.7; valence 4. See Periodic Table.
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