Definition of energy
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 (as heat or electricity); also : the resources for producing such power
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.
Origin and Etymology of energy
Late Latin energia, from Greek energeia activity, from energos active, from en in + ergon work — more at work
First Known Use: 1599
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>.
ENERGY Defined for English Language Learners
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.
ENERGY Defined for Kids
Definition of energy for Students
1 : ability to be active : strength of body or mind to do things or to work <The children … were tired and hardly had energy enough to walk. — E. B. White, Charlotte's Web>
2 : strong action or effort <He puts a lot of energy into his work.>
3 : usable power or the resources (as oil) used to produce usable power <Our new dryer uses a lot less energy.>
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