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Added 2 October 2026

energy

/ˈɛnəd͡ʒi/ noun

In Latin: nāvitās Coined: 1802, by Thomas Young Wiktionary

noun Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about energy at Wordnik → Where our words come from →

The impetus behind all motion and all activity.
The capacity to do work.
A quantity that denotes the ability to do work and is measured in a unit dimensioned in mass × distance²/time² (ML²/T²) or the equivalent.
Units:

Origin

From Middle French énergie, from Late Latin energia, from Ancient Greek ἐνέργεια (enérgeia, “activity”), from ἐνεργός (energós, “active”), from ἐν (en, “in”) + ἔργον (érgon, “work”). The sense in physics was coined by English polymath Thomas Young in 1802 in his lectures on Natural Philosophy.

From Wiktionary, via Kaikki.org (CC BY-SA)

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