¹quantum

noun quan·tum \ˈkwän-təm\

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

plural quan·ta \ˈkwän-tə\

Full Definition of QUANTUM

a : quantity, amount

b : portion, part

c : gross quantity : bulk

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 (as magnetic moment)

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Origin of QUANTUM

Latin, neuter of quantus how much

First Known Use: 1567

Related to QUANTUM

Synonyms: measure, quantity, amount, volume

Other Physics Terms

amplitude, centrifugal, centripetal, convection, gradient, hysteresis, kinetic, lase

²quantum

adjective

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

Full Definition of QUANTUM

: large, significant <a quantum improvement>

: of, relating to, or employing the principles of quantum mechanics <quantum physics>

See quantum defined for English-language learners

First Known Use of QUANTUM

1942

Other Physics Terms

amplitude, centrifugal, centripetal, convection, gradient, hysteresis, kinetic, lase, quantum

Medical Dictionary

quantum

noun quan·tum \ˈkwänt-əm\

plural quan·ta \ˈkwänt-ə\

Medical Definition of QUANTUM

: 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>

: 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