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English definition of “energy”


noun  /ˈen·ər·dʒi/ us  

energy noun (STRENGTH)

the power and ability to be physically and mentally active: [U] They spent a lot of time and energy on the grant proposal. [U] He wrote with a great burst of energy. Your energies are the total amount of your physical and mental strength to do something: [pl] All my energies were directed toward establishing an academic career.

energy noun (POWER)

physics [U] power to do work that produces light, heat, or motion, or the fuel or electricity used for power: Certain materials acquired the ability to carry an electric charge with no loss of energy. The cost of energy rose last month.
(Definition of energy from the Cambridge Academic Content Dictionary © Cambridge University Press)
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