Did you know?

Click any word in a definition or example to find the entry for that word

energy - definition and synonyms

What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

Thesaurus diagram

The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

noun     energy pronunciation in British 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] science 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

deep learning

a form of machine learning which incorporates the use of neural networks

BuzzWord Article

Open Dictionary

snap election

a general election … that is called earlier than expected

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play