The story
- Proto-Indo-European*h₁én
- Ancient Greekἐν (en)
- Ancient Greekἐν- (en-)
- Proto-Indo-European*werǵ-
- Proto-Indo-European*wérǵom
- Proto-Hellenic*wérgon
- Ancient Greekἔργον (érgon)
- Ancient Greekἐνεργός (energós)
- Ancient Greekἐνεργής (energḗs)
- Ancient Greekἐνέργεια (enérgeia)
- Late Latinenergīa
- Middle Frenchénergie
- Englishenergy
- Englishenergize
- English todayenergizer
From energize + -er.
Etymology from Wiktionary, CC BY-SA 4.0.