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quantum

[ kwon-tuhm ]
/ ˈkwɒn təm /
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See synonyms for: quantum / quanta on Thesaurus.com

noun, plural quan·ta [kwon-tuh]. /ˈkwɒn tə/.
quantity or amount: the least quantum of evidence.
a particular amount.
a share or portion.
a large quantity; bulk.
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.
adjective
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
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use quantum in a sentence

British Dictionary definitions for quantum

quantum
/ (ˈkwɒntəm) /

noun plural -ta (-tə)
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
amount or quantity, esp a specific amount
(often used with a negative) the least possible amount that can sufficethere is not a quantum of evidence for your accusation
something that can be quantified or measured
(modifier) loosely, sudden, spectacular, or vitally importanta quantum improvement

Word Origin for quantum

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

Scientific definitions for quantum

quantum
[ kwƏnâ€Čtəm ]

Plural quanta
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.
The American HeritageŸ Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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