TM Unabridged


Symbol, Chemistry.


true mean. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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World English Dictionary
the internet domain name for

the chemical symbol for

abbreviation for
1.  transcendental meditation
2.  Turkmenistan (international car registration)

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
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American Heritage
Medical Dictionary

tm abbr.
temperature midpoint (on the Celsius scale)

Tm 1

The symbol for the element thulium.

Tm 2

  1. transport maximum

  2. tubular maximum

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
The symbol for thulium.
thulium   (th'lē-əm)  Pronunciation Key 
Symbol Tm
A soft, silver-gray metallic element of the lanthanide series. One of its artificial radioactive isotopes is used as a radiation source in small, portable x-ray machines. Atomic number 69; atomic weight 168.934; melting point 1,545°C; boiling point 1,727°C; specific gravity 9.3; valence 2, 3. See Periodic Table.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Computing Dictionary

TM definition

1. Turing Machine.
2. A formal database specification language.
[Jargon File]

tm definition

The country code for Turkmenistan.
Heavily used for vanity domains because it looks like the abbreviation for "trademark".
The Free On-line Dictionary of Computing, © Denis Howe 2010
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American Heritage
Abbreviations & Acronyms
  1. thulium

  2. Timothy

  1. telemetry

  2. them (shortwave transmission)

  3. trademark

  4. transcendental meditation

  5. true mean

  6. Turkmenistan (international vehicle ID)

  7. tympanic membrane

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The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Encyclopedia Britannica


(Tm), chemical element, rare-earth metal of the lanthanoid series of the periodic table. One of the rarest of the rare-earth elements, though more abundant than silver, thulium has few commercial uses. Natural thulium is wholly composed of the stable isotope thulium-169. Bombarded by neutrons, it becomes radioactive thulium-170 (128-day half-life), which ejects soft gamma radiation (0.084 million electron volts) resembling an X ray. It is useful in small portable X-ray units suitable for photographing bony tissues and for examining thin-walled machine parts and has been used by archaeologists to examine markings and symbols on ancient metallic artifacts.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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