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

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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 Canberra will additionally benefit from greater sharing of intelligence and collaboration in sensitive fields including cyber warfare, AI, quantum computing, and more. Time, 28 Sep. 2021 In other news, Microsoft’s 2018 claims of having discovering evidence of an elusive particle, called a Majorana Fermion, which is key to its quantum computing endeavors, were apparently bunk, Wired reports. Robert Hackett, Fortune, 9 Mar. 2021 The $30 amount matched the quantum of equivalent coin that El Salvador promised to put into every citizen’s digital wallet. Samanth Subramanian, Quartz, 9 Sep. 2021 In 2020, the Trump administration announced $1 billion in funding for artificial intelligence and quantum computing research. Lillian Reed, baltimoresun.com, 8 Sep. 2021 Teaching critical race theory in K-12 would be like teaching quantum physics in K-12. Brandon Tensley, CNN, 2 Sep. 2021 Third, how a potential quantum computer neural simulation is set up might be able to take advantage of the physics the brain is subject to. Gabriel A. Silva, Forbes, 3 Sep. 2021 Physicists like Nobel laureate Frank Wilczek are trying to figure out how to make a practical topological quantum computer on Earth. Stephon Alexander, Wired, 31 Aug. 2021 In 2019, Google announced that its Sycamore quantum computer had completed a task in 200 seconds that would take a conventional computer 10,000 years. Quanta Magazine, 2 Aug. 2021 Recent Examples on the Web: Adjective With a quantum travel theme, Meow Wolf, an immersive arts and entertainment company, has opened its newest (and most ambitious) mind-bending attraction in Denver. Brittany Anas, Forbes, 1 Oct. 2021 One promising area is hypersonics; another is AI; still another is quantum, where the four Quad nations plus South Korea can bring extensive expertise to the post-digital technology that will dominate the 21st century. Arthur Herman, National Review, 1 Oct. 2021 Superdeterminism attempts to eliminate several puzzling features of quantum mechanics, including the apparent randomness of quantum events and intrusive role of measurement. John Horgan, Scientific American, 27 Sep. 2021 Feeding into an open source platform to allow the global community to participate, they will be supported by a quantum computer, a new type of computer that employs the properties of quantum mechanics to achieve incredible speed and power. Jacopo Prisco, CNN, 27 Sep. 2021 But the results may not be as accurate as what can be achieved with a quantum computer. Jeremy Kahn, Fortune, 22 Sep. 2021 So, why are IonQ and other quantum computer companies so interested in increasing the number of qubits? Paul Smith-goodson, Forbes, 14 Sep. 2021 However, a quantum computer could select the shortest straw by examining all of them simultaneously to determine length — not unlike how a human is capable of picking out the shortest straw by sight. Lillian Reed, baltimoresun.com, 8 Sep. 2021 What is a quantum computer, and why would aliens be using them? Stephon Alexander, Wired, 31 Aug. 2021

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.

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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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Learn More About quantum

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

5 Oct 2021

Cite this Entry

“Quantum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quantum. Accessed 15 Oct. 2021.

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More Definitions for quantum



English Language Learners Definition of quantum

 (Entry 1 of 2)

: the smallest amount of many forms of energy (such as light)



English Language Learners Definition of quantum (Entry 2 of 2)

: of, relating to, or using the principles of quantum theory


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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