quantum

1 of 2

noun

quan·​tum ˈkwän-təm How to pronounce quantum (audio)
plural quanta ˈkwän-tə How to pronounce quantum (audio)
Synonyms of quantumnext
1
a
: quantity, amount
b
: portion, part
c
: gross quantity : bulk
2
a
: 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)

quantum

2 of 2

adjective

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

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
As innovative technologies like artificial intelligence and quantum computing advance in capabilities and comprehension, 2025 will see a variety of both old and new cyberthreats. — Chuck Brooks, Forbes.com, 5 Apr. 2025 Since then, physicists have exploited these non-linear optics in techniques ranging from precision measurement to quantum computing. — The Physics Arxiv Blog, Discover Magazine, 31 Mar. 2025
Adjective
Ewin Tang, for developing classical analogs of quantum algorithms for machine learning and linear algebra, and for advances in quantum machine learning on quantum data. — Alex Cramer, HollywoodReporter, 6 Apr. 2025 Physicists have found it in collections of quantum particles, along with classical systems like swirling ocean currents. — Charlie Wood, Wired News, 6 Apr. 2025 See All Example Sentences for quantum

Word History

Etymology

Noun

Latin, neuter of quantus how much

First Known Use

Noun

1567, in the meaning defined at sense 1a

Adjective

1942, in the meaning defined at sense 1

Time Traveler
The first known use of quantum was in 1567

Phrases Containing quantum

Rhymes for quantum

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Browse Nearby Words

quantong
quantum
quantum chromodynamics
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Cite this Entry

“Quantum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quantum. Accessed 13 Apr. 2025.

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Kids Definition

quantum

1 of 2 noun
quan·​tum ˈkwänt-əm How to pronounce quantum (audio)
plural quanta ˈkwänt-ə How to pronounce quantum (audio)
: the smallest amount of many forms of energy (as light)

quantum

2 of 2 adjective
: of or relating to the principles of quantum theory
quantum physics

Medical Definition

quantum

noun
quan·​tum ˈkwänt-əm How to pronounce quantum (audio)
plural quanta ˈkwänt-ə How to pronounce quantum (audio)
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.com: Encyclopedia article about quantum

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