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Biochemistry. adenosine triphosphate: an ester of adenosine and triphosphoric acid, C 10 H 12 N 5 O 4 H 4 P 3 O 9 , formed especially aerobically by the reaction of ADP and an orthophosphate during oxidation, or by the interaction of ADP and phosphocreatine or certain other substrates, and serving as a source of energy for physiological reactions, especially muscle contraction.
Origin of ATP
First recorded in 1940-45 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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  • It was very amusing to see the attention bestowed upon him ATP.

    Wild Nature Won By Kindness Elizabeth Brightwen
  • Boys was only a fellow-student, whose acquaintance Erasmus had made ATP 104 Montaigu.

    The Age of Erasmus P. S. Allen
British Dictionary definitions for ATP


adenosine triphosphate; a nucleotide found in the mitochondria of all plant and animal cells. It is the major source of energy for cellular reactions, this energy being released during its conversion to ADP. Formula: C10H16N5O13P3


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Association of Tennis Professionals
automatic train protection: a safety system which automatically prevents a train from passing through a stop signal
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
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Word Origin and History for ATP

abbreviation of adenosine triphosphate, attested from 1939.

Online Etymology Dictionary, © 2010 Douglas Harper
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ATP in Medicine

ATP (ā'tē'pē')
Adenosine triphosphate; an adenosine-derived nucleotide that supplies large amounts of energy to cells for various biochemical processes, including muscle contraction and sugar metabolism, through its hydrolysis to ADP.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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ATP in Science
Short for adenosine triphosphate. An organic compound, C10H16N5O13P3, that is composed of adenosine and three phosphate groups. It serves as a source of energy for many metabolic processes. ATP releases energy when it is broken down into ADP by hydrolysis during cell metabolism.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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ATP in Culture
ATP (adenosine triphosphate)

A key energy-carrying molecule in biological systems. It is produced in the body through the process of cell respiration and in plants through photosynthesis.

The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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