1

quantum

noun quan·tum \ ˈkwän-təm \
|Updated on: 18 Jul 2018
plural quanta play \ˈkwän-tə\
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)

Examples of quantum in a Sentence

  1. 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 of quantum from the Web

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.

Origin and Etymology of quantum

Latin, neuter of quantus how much

quantum Synonyms

Synonyms

amount, measure, quantity, volume;

Related Words

coefficient, degree;

body, portion;

many, number;


2

quantum

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

Recent Examples of quantum from the Web

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

1942

in the meaning defined at sense 1

See Words from the same year
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QUANTUM Defined for English Language Learners

quantum

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


quantum

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


Medical Dictionary

quantum

noun quan·tum \ ˈkwänt-əm \
plural quanta play \ˈkwänt-ə\
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


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