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quantum

[kwon-tuh m]
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noun, plural quan·ta [kwon-tuh] /ˈkwɒn tə/.
  1. quantity or amount: the least quantum of evidence.
  2. a particular amount.
  3. a share or portion.
  4. a large quantity; bulk.
  5. Physics.
    1. the smallest quantity of radiant energy, equal to Planck's constant times the frequency of the associated radiation.
    2. the fundamental unit of a quantized physical magnitude, as angular momentum.
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adjective
  1. sudden and significant: a quantum increase in productivity.
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Origin of quantum

1610–20; noun use of neuter of Latin quantus how much

quantum sufficit

[kwahn-too m soof-i-kit; English kwon-tuh m suhf-uh-sit]
adverb Latin.
  1. as much as suffices; enough.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for quantum

quantum

noun plural -ta (-tə)
  1. physics
    1. the smallest quantity of some physical property, such as energy, that a system can possess according to the quantum theory
    2. a particle with such a unit of energy
  2. amount or quantity, esp a specific amount
  3. (often used with a negative) the least possible amount that can sufficethere is not a quantum of evidence for your accusation
  4. something that can be quantified or measured
  5. (modifier) loosely, sudden, spectacular, or vitally importanta quantum improvement
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Word Origin

C17: from Latin quantus (adj) how much
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

Word Origin and History for quantum

n.

1610s, "one's share or portion," from Latin quantum (plural quanta) "as much as, so much as; how much? how far? how great an extent?" neuter singular of correlative pronomial adjective quantus "as much" (see quantity). Introduced in physics directly from Latin by Max Planck, 1900; reinforced by Einstein, 1905. Quantum theory is from 1912; quantum mechanics, 1922; quantum jump is first recorded 1954; quantum leap, 1963, often figurative.

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Online Etymology Dictionary, © 2010 Douglas Harper

quantum in Medicine

quantum

(kwŏntəm)
n. pl. quan•ta (-tə)
  1. The smallest amount of a physical quantity that can exist independently, especially a discrete quantity of electromagnetic radiation.
  2. This amount of energy regarded as a unit.
  3. A quantity or an amount.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

quantum in Science

quantum

[kwŏntəm]
Plural quanta
  1. A discrete, indivisible manifestation of a physical property, such as a force or angular momentum. Some quanta take the form of elementary particles; for example, the quantum of electromagnetic radiation is the photon, while the quanta of the weak force are the W and Z particles. See also quantum state.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.