quan·​tum | \ ˈkwän-təm How to pronounce quantum (audio) \
plural quanta\ ˈkwän-​tə How to pronounce quantum (audio) \

Definition of quantum

 (Entry 1 of 2)

b : portion, part
c : gross quantity : bulk
2a : any of the very small increments or parcels into which many forms of energy are subdivided
b : any of the small subdivisions of a quantized physical magnitude (such as magnetic moment)



Definition of quantum (Entry 2 of 2)

1 : large, significant a quantum improvement
2 : of, relating to, or employing the principles of quantum mechanics quantum physics

Synonyms for quantum

Synonyms: Noun

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Examples of quantum in a Sentence

Noun the sum of human knowledge is now so immense that even a highly educated person can hope to absorb only a tiny quantum of it
Recent Examples on the Web: Noun In the last few years the flood of venture capital dollars into the quantum sector has been extraordinary, some $3 billion in 2021 alone. Arthur Herman, Forbes, 19 May 2022 These quantum fields overlap each other and interact in complicated, interesting ways. Paul Sutter, Ars Technica, 18 May 2022 The quantum physicists Sandu Popescu, Yakir Aharonov and Daniel Rohrlich have been troubled by the same scenario for three decades. Katie Mccormick, Quanta Magazine, 16 May 2022 Yet quantum-leaping drawbacks are even more visceral in the six-part series, kicking off Sunday (9 EDT/ PDT), in which Henry often vomits after arriving in a new time period. Bryan Alexander, USA TODAY, 13 May 2022 Endgame following the five years that her father was trapped in the quantum realm. Christian Holub, EW.com, 8 May 2022 Next, the researchers want to test this method for long-distance quantum cryptography. Caroline Delbert, Popular Mechanics, 29 Apr. 2022 Although Pritchard’s queen appears simultaneously present and absent, this is neither a quantum paradox nor image manipulation. Susana Martinez-conde, Scientific American, 26 Apr. 2022 Beyond the numbers, New Orleans is winning the physicality battle that has Chris Paul wondering if he's entered Marvel's quantum realm and traveled back in time. Duane Rankin, The Arizona Republic, 25 Apr. 2022 Recent Examples on the Web: Adjective Japan will ban the export of high-tech goods including quantum computers, printers and electron microscopes to Russia starting May 20. Yuliya Talmazan, NBC News, 12 May 2022 The conflict is on full display in black holes, which deform space so severely that gravity’s more fundamental, quantum nature cannot be ignored. Quanta Magazine, 20 Apr. 2022 Rubino’s team looked at a quantum superposition with a state that evolves both backward and forward in time. Stav Dimitropoulos, Popular Mechanics, 22 Apr. 2022 Swingle wanted to reverse time in order to study black holes and a quantum phenomenon known as scrambling. Quanta Magazine, 7 Sep. 2021 These quantum dots can essentially produce a brighter image and deeper colors. Maren Estrada, BGR, 18 July 2021 In their paper, the GHZ state involved entangling four qubits such that the entire system was in a two-dimensional quantum superposition of states 0000 and 1111. Anil Ananthaswamy, Scientific American, 2 July 2021 In addition, companies may focus on post-quantum security, leveraging cryptographic algorithms in their systems. Dan Weil, WSJ, 9 Mar. 2021 Qubits tend to be unstable, but in an ideal world each additional one adds exponential power to a quantum machine. Robert Hackett, Fortune, 1 Oct. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'quantum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of quantum


1567, in the meaning defined at sense 1a


1942, in the meaning defined at sense 1

History and Etymology for quantum


Latin, neuter of quantus how much

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Time Traveler for quantum

Time Traveler

The first known use of quantum was in 1567

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Dictionary Entries Near quantum



quantum chromodynamics

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Statistics for quantum

Last Updated

26 May 2022

Cite this Entry

“Quantum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quantum. Accessed 29 May. 2022.

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More Definitions for quantum


quan·​tum | \ ˈkwänt-əm How to pronounce quantum (audio) \
plural quanta\ ˈkwänt-​ə How to pronounce quantum (audio) \

Medical Definition of quantum

1 : one of the very small increments or parcels into which many forms of energy are subdivided a molecule of rhodopsin in the human eye can cause a response to a single quantum of light
2 : one of the small molecular packets of a neurotransmitter (as acetylcholine) released into the synaptic cleft in the transmission of a nerve impulse across a synapse

More from Merriam-Webster on quantum

Nglish: Translation of quantum for Spanish Speakers

Britannica English: Translation of quantum for Arabic Speakers

Britannica.com: Encyclopedia article about quantum


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