energy

noun

en·​er·​gy ˈe-nər-jē 

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

Synonyms

• qi
• aura
• spirit
• chi
• life
• light
• ki

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

Corn can provide carbohydrates, which can be vital to deer during the winter for a burst of energy, Edge said, but an increase in carbs can disrupt the animal's gut chemistry and affect digestion, much like giving children a lot of candy bars. —Craig Shoup, Nashville Tennessean, 27 Oct. 2025

Tokyo has pledged to reduce the reliance, but says an abrupt cutoff could threaten its energy security. —Hanako Montgomery, CNN Money, 27 Oct. 2025

Upcycling solid wastes This technique provides a versatile, scalable, and efficient strategy for upcycling solid wastes into high-performance materials for environmental and energy catalysis, as per the study. —Prabhat Ranjan Mishra, Interesting Engineering, 27 Oct. 2025

When the lines of a CME’s magnetic field and those of the Earth’s magnetic field are pointed in the opposite directions, the CME can unite with the Earth’s magnetosphere and fill it with vast quantities of solar energy. —Literary Hub, 27 Oct. 2025

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

Phrases Containing energy

• activation energy
• alternative energy
• atomic energy
• binding energy
• bundle of energy
• conservation of energy
• dark energy
• dual energy X-ray absorptiometry
• energy drink
• energy level
• high-energy
• high-energy physics
• kinetic energy
• luminous energy
• nervous energy
• non-energy
• nuclear energy
• potential energy
• radiant energy

Rhymes for energy

• bioenergy

Kids Definition

energy

noun

en·​er·​gy ˈen-ər-jē 

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 

plural energies

1

: psychic energy

2

: the capacity for doing work