thorium


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tho·ri·um

 (thôr′ē-əm)
n. Symbol Th
A radioactive silvery-white metallic element that is recovered commercially from monazite. Its longest-lived isotope, the only one that occurs naturally, is Th-232 with a half-life of 14.1 billion years and is used as a nuclear fuel. Thorium is used in magnesium alloys, and its oxide is widely used in gas mantles of Welsbach burners. Atomic number 90; atomic weight 232.038; melting point 1,750°C; boiling point 4,788°C; specific gravity 11.72; valence 4. See Periodic Table.

[After Thor.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

thorium

(ˈθɔːrɪəm)
n
(Elements & Compounds) 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]
ˈthoric adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

tho•ri•um

(ˈθɔr i əm, ˈθoʊr-)

n.
a grayish white, lustrous, radioactive metallic element: used as a source of nuclear energy, in sun-lamp and vacuum-tube filaments, and in alloys. Symbol: Th; at. wt.: 232.038; at. no.: 90; sp. gr.: 11.7.
[< Swedish (1829); see Thor, -ium2]
thor•ic (ˈθɔr ɪk, ˈθɒr-) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

tho·ri·um

(thôr′ē-əm)
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 is also its most stable, having a half-life of 14 billion years. Atomic number 90. See Periodic Table.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.thorium - a soft silvery-white tetravalent radioactive metallic elementthorium - a soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands
metal, metallic element - any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.
radiothorium, thorium-228 - radioactive isotope of thorium with mass number 228
monazite - a reddish-brown mineral containing rare earth metals; an important source of thorium and cerium
thorite - a radioactive mineral consisting of thorium silicate; it is a source of thorium that is found in coarse granite
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
Translations
торий
thorium
thorium
torio
toorium
torium
תוריום
torij
tórium
þórín
トリウム
thorium
toris
thorium
thorium
torij
torium
toryum

thorium

[ˈθɔːrɪəm] Ntorio m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

thorium

n (Chem) → Thorium nt
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
References in periodicals archive ?
Thorium also warned there was a threat of further regulation in the sector,including a potential smoking ban in UK pubs and ongoing scrutiny of alcohol consumption by the Government.
My Favourite Song by Thorium is mostly very good but does slip into moments of hardcore by numbers, while I'm Spartacus provide what is for me the only lowpoint with Poster.
Natural thorium consists of the fertile isotope Th-232, which is converted to fissile U-233 in a reactor.
Specialists are asking not to ban thorium mining, because it is not that harmful like uranium, PM said.
Prof Cywinski's pet project the Thorium reactor is still largely untested, not proven in practice, would involve huge funding and wouldn't come on-stream in this country for probably another 30 years which is simply too late.
Investment in renewables without storage may help meet short-term targets while delaying the development of technologies likely to be cheaper and more effective in the long term--such as reactors using molten thorium and current radioactive waste as fuel.
The company dumped thorium and some uranium into the sewer system as waste byproducts until 1947, when the Atomic Energy Commission, the successor of the Manhattan Project, began buying thorium for research, according to government documents.
By comparing expected ratios of thorium and protactinium in those ocean sediments to observed amounts, the authors showed that protactinium was being swept out of the Arctic before it could settle to the ocean bottom.
Ban also applies to import of uranium, said MP Almambet Shykmamatov during the parliament consideration of the draft law banning exploration and mining of uranium and thorium deposits in Kyrgyzstan.
As monazite is an important source of rare earth elements and contains thorium, a naturally occurring radioactive metal, monazite was considered an important national defense resource.