1

quantum

noun quan·tum \ ˈkwän-təm \
Updated on: 16 Nov 2017

Definition of quantum

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


2

quantum

adjective

Definition of quantum

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


QUANTUM Defined for English Language Learners

quantum

noun

Definition of quantum for English Language Learners

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


quantum

adjective

Definition of quantum for English Language Learners

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


Medical Dictionary

quantum

noun quan·tum \ ˈkwänt-əm \

medical Definition of quantum

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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