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energy - definition and synonyms

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noun     energy pronunciation in American English
Word Forms
  1. 1
    [uncountable] a supply of physical power that you have for doing things that need physical effort

    As children we seemed to have endless energy.

    She didn’t even have the energy to get out of bed.

    1. a.
      [countable/uncountable] enthusiasm and determination

      She could offer youthful energy and talent in abundance.

      put/devote/throw your energy/energies into something:

      Christine threw her energies into her teaching.

  2. 2
    [uncountable] a form of power such as electricity, heat, or light that is used for making things work

    Insulating your home is a good way to save energy.

    1. a.
      science the power that is present in all physical things and that can be changed into something such as heat, movement, or light


a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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