energy

noun

en·​er·​gy ˈe-nər-jē How to pronounce energy (audio)
plural energies
1
a
: dynamic quality
narrative energy
b
: the capacity of acting or being active
intellectual energy
c
: a usually positive spiritual force
the energy flowing through all people
2
: vigorous exertion of power : effort
investing time and energy
3
: a fundamental entity of nature that is transferred between parts of a system in the production of physical change within the system and usually regarded as the capacity for doing work
4
: usable power (such as heat or electricity)
also : the resources for producing such power
Choose the Right Synonym for energy

power, force, energy, strength, might mean the ability to exert effort.

power may imply latent or exerted physical, mental, or spiritual ability to act or be acted upon.

the awesome power of flowing water

force implies the actual effective exercise of power.

used enough force to push the door open

energy applies to power expended or capable of being transformed into work.

a worker with boundless energy

strength applies to the quality or property of a person or thing that makes possible the exertion of force or the withstanding of strain, pressure, or attack.

use weight training to build your strength

might implies great or overwhelming power or strength.

the belief that might makes right

Examples of energy in a Sentence

The kids are always so full of energy. They devoted all their energy to the completion of the project. They devoted all their energies to the completion of the project. She puts a lot of energy into her work. The newer appliances conserve more energy.
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.
Moscow regaining its status as Europe's top energy supplier would hurt American oil and gas producers, especially as the U.S. has made inroads as an LNG supplier there. Thomas G. Moukawsher, MSNBC Newsweek, 24 Apr. 2025 During ketosis, the body burns fat for energy instead of sugar. Chelsea Rae Bourgeois, Rdn, Health, 24 Apr. 2025 One aim was to gather data on how seismic energy from earthquakes reverberated through the Earth’s crust and upper mantle. Alexandra Witze, JSTOR Daily, 24 Apr. 2025 Understanding and protecting your energy is key at any stage in your career. Ivan Terzi, Forbes.com, 24 Apr. 2025 See All Example Sentences for energy

Word History

Etymology

Late Latin energia, from Greek energeia activity, from energos active, from en in + ergon work — more at work

First Known Use

1783, in the meaning defined at sense 1a

Time Traveler
The first known use of energy was in 1783

Browse Nearby Words

Cite this Entry

“Energy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/energy. Accessed 29 Apr. 2025.

Kids Definition

energy

noun
en·​er·​gy ˈen-ər-jē How to pronounce energy (audio)
plural energies
1
: power or ability to be active : strength of body or mind to do things or to work
a teacher of great intellectual energy
2
: natural power exerted with force : lively action
work with energy
3
: the capacity (as of heat, light, or running water) for doing work
4
a
: usable power (as heat or electricity)
b
: a source of energy
especially : a resource (as oil) used to provide energy

Medical Definition

energy

noun
en·​er·​gy ˈen-ər-jē How to pronounce energy (audio)
plural energies
1
2
: the capacity for doing work

More from Merriam-Webster on energy

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