エネルギー
Confidentenerugi
energy
katakana
Origin
- Source language
- German (de)
- Source form
- Energie
- Borrowing route
- ドイツ語学術語 → 近代日本語
- Semantic shift
- 物理学のエネルギー → 体力・活力の比喩にも拡張
- First attested
- 1880
Story
1895 is an early Japanese printed point for エネルギー: 精選版日本国語大辞典 cites Uchida Roan's Sengo no Bungaku with the older spelling ヱネルギー. The source form is German Energie. Duden traces Energie through French énergie and Late Latin energia to Greek energeia, activity or effective force, from ergon, work. The Japanese spelling shifted from ヱ to エ after script reforms in the twentieth century.
The borrowing entered Meiji academic Japanese through physics and general science. In dictionaries it first names the physical capacity to do work, measured by units such as エルグ and ジュール, and used in compounds like 運動エネルギー and ポテンシャルエネルギー. School chemistry added 化学エネルギー, and engineering added 電気エネルギー. The word later appeared in public policy and daily life; after the 1973 oil crisis, エネルギー問題 became a common newspaper phrase in Japan.
Today エネルギー covers physics, fuel, calories, stamina, and motivation. The sound follows German Energie more than English energy, whose middle consonant is /dʒ/. 今日はエネルギーがない can mean low physical strength or drive, while a physics textbook still uses エネルギー for measurable work capacity. English also has wider uses, but the Japanese pronunciation is the main etymological clue.