energy

noun en·er·gy \ ˈe-nər-jē \

|Updated on: 8 Aug 2018

Tip: Synonym Guide

Examples: energy in a Sentence

Definition of energy

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

See energy defined for English-language learners

See energy defined for kids

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 of energy from the Web

Inside, there was the hectic, confused energy of a field hospital run mostly by non-doctors.

— joshua partlow, chicagotribune.com, "Inside the church where Nicaraguan paramilitaries laid siege on university students," 14 July 2018
Let the energy of the moment before the leap course through your body.

— bess matassa, Teen Vogue, "Weekly Horoscopes July 16-22," 13 July 2018
Fuel cells typically use the energy stored in chemical bonds to make electricity; MacFarlane's operates in reverse.

— robert f. service, Science | AAAS, "Ammonia—a renewable fuel made from sun, air, and water—could power the globe without carbon," 12 July 2018
Major changes come in minute steps — and the energy of the new moon recognizes that.

— refinery29.com, "What It Means If Your New Moon Is Decidedly Not Chill," 12 July 2018
The cast keeps up the energy with clever use of the multilevel set, percussive instruments, and audience interaction in the aisles.

— marissa oberlander, Chicago Reader, "Chicago Shakespeare’s Peter Pan is a soaring delight for both kids and adults," 11 July 2018
Some have set targets for buying renewable energy and reducing their carbon footprints.

— mark trumbull, The Christian Science Monitor, "From new leadership to Clean Power Plan, subtle shifts ripple through EPA," 11 July 2018
For instance, the asteroid that hit over the Russian city of Chelyabinsk — that particular asteroid exploded, and the energy of that explosion was about 30 times the size of the nuclear bomb dropped over Hiroshima.

— NBC News, "Stopping 'Armageddon': This former astronaut is on a mission to save Earth from deadly asteroids," 10 July 2018
The energy of a photon gets absorbed by an electron in the material which then jumps, leaving behind a hole.

— charles w. dunnill, Scientific American, "Method of Making Oxygen from Water in Zero Gravity Raises Hope for Long-Distance Space Travel," 10 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'energy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of energy

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

NEW! Time Traveler

First Known Use: 1599

in the meaning defined at sense 1a

See Words from the same year

energy Synonyms

Synonym Discussion of 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

Other Physics Terms

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

ENERGY Defined for English Language Learners

energy

noun

Definition of energy for English Language Learners

: ability to be active : the physical or mental strength that allows you to do things
: natural enthusiasm and effort
: usable power that comes from heat, electricity, etc.