[ tek-nee-shee-uh m, -shuh m ]
/ tɛkˈni ʃi əm, -ʃəm /
Chemistry. an element of the manganese family, not found in nature, but obtained in the fission of uranium or by the bombardment of molybdenum. Symbol: Tc; atomic weight: 99; atomic number: 43; specific gravity: 11.5.
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British Dictionary definitions for technetium
/ (tɛkˈniːʃɪəm) /
a silvery-grey metallic element, artificially produced by bombardment of molybdenum by deuterons: used to inhibit corrosion in steel. The radioisotope technetium-99m, with a half-life of six hours, is used in radiotherapy. Symbol: Tc; atomic no: 43; half-life of most stable isotope, 97 Tc: 2.6 × 10 6 years; valency: 0, 2, 4, 5, 6, or 7; relative density: 11.50 (calculated); melting pt: 2204°C; boiling pt: 4265°C
Word Origin for technetium
C20: New Latin, from Greek tekhnētos manmade, from tekhnasthai to devise artificially, from tekhnē skill
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medicine definitions for technetium
[ tĕk-nē′shē-əm, -shəm ]
n. Symbol Tc
A radioactive metal, the first synthetically produced element, used as a tracer and in diagnostic imaging. Atomic number 43.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Science definitions for technetium
[ tĕk-nē′shē-əm ]
A silvery-gray, radioactive metallic element. It was the first element to be artificially made, and it is produced naturally in extremely small amounts during the radioactive decay of uranium. Technetium is used to remove corrosion from steel. Its longest-lived isotope is Tc 98 with a half-life of 4,200,000 years. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7. See Periodic Table.
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