Definition of energy
1a : dynamic quality narrative energyb : the capacity of acting or being active intellectual energyc : 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
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
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.
Seen and Heard
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