thallium
[ thal-ee-uhm ]
/ ˈθæl i əm /
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noun Chemistry.
a soft, malleable, rare, bluish-white metallic element: used in the manufacture of alloys and, in the form of its salts, in rodenticides. Symbol: Tl; atomic weight: 204.37; atomic number: 81; specific gravity: 11.85 at 20°C.
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Origin of thallium
1860–65; <New Latin, equivalent to thall- (<Greek thallós green stalk) + -ium-ium; named after green line in its spectrum
Words nearby thallium
Thales, thali, Thalia, thalidomide, thallic, thallium, thallium sulfate, thallo-, thalloid, thallophyte, thallous
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for thallium
British Dictionary definitions for thallium
thallium
/ (ˈθælɪəm) /
noun
a soft malleable highly toxic white metallic element used as a rodent and insect poison and in low-melting glass. Its compounds are used as infrared detectors and in photoelectric cells. Symbol: Tl; atomic no: 81; atomic wt: 204.3833; valency: 1 or 3; relative density: 11.85; melting pt: 304°C; boiling pt: 1473±10°C
Word Origin for thallium
C19: from New Latin, from Greek thallos a green shoot; referring to the green line in its spectrum
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Medical definitions for thallium
thallium
[ thăl′ē-əm ]
n. Symbol Tl
A soft, malleable, highly toxic metallic element whose radioisotopes are used in diagnostic imaging. Atomic number 81.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for thallium
thallium
[ thăl′ē-əm ]
Tl
A soft, malleable, very poisonous metallic element that is used in photography, in making low-melting and highly refractive glass, and in treating skin infections. Atomic number 81; atomic weight 204.38; melting point 303.5°C; boiling point 1,457°C; specific gravity 11.85; valence 1, 3. See Periodic Table.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.