Translation guide
The English word 'energy' covers physical vitality, power resources, and a sense of lively force. This guide helps learners choose the right Japanese expression for each meaning.
The strength and endurance to do things, often related to health or tiredness.
The most common word for physical and mental well-being, vitality, or being in good spirits. Often used in greetings and daily conversation.
元気ですか？
How are you? (lit. Are you energetic/well?)
今日は元気がないね。
You seem low on energy today.
Physical strength or stamina, often used in contexts of exercise, work, or aging.
体力をつけるために運動している。
I exercise to build up my stamina.
最近、体力が落ちた。
Lately, my physical energy has declined.
Vigor or vitality, often with a nuance of drive or sexual energy. Can sound formal or literary.
彼は仕事に精力を注いでいる。
He pours his energy into his work.
Sources of power such as electricity, gas, or renewable energy.
The direct loanword for 'energy' in scientific, technical, and everyday contexts about power resources. Used for electricity, fuel, renewable energy, etc.
再生可能エネルギーを増やす必要がある。
We need to increase renewable energy.
エネルギーを節約しましょう。
Let's save energy.
Motive power, often mechanical or engine-driven. Used in engineering contexts.
A dynamic quality of being active, enthusiastic, or full of life.
Liveliness, vibrancy, or bustle. Often used for places, events, or groups.
この街は活気にあふれている。
This town is full of energy.
会議は活気がなかった。
The meeting lacked energy.
Force, momentum, or vigor. Can describe a person's energetic action or the impetus of a movement.
Vitality, life force. Slightly more abstract and often used in self-help or health contexts.
The scientific concept of energy as a measurable quantity.
The standard term in physics for energy (kinetic, potential, etc.).
エネルギー保存の法則
the law of conservation of energy
Use 元気 for personal vitality and well-being. Use エネルギー for power resources and physics. Saying エネルギーがある for a person is possible but sounds like 'I have a lot of drive/power' rather than 'I'm well.'
元気いっぱいの子ども
a child full of energy (vitality)
エネルギー資源
energy resources
この機械は電気を動力としている。
This machine uses electricity as its power source.
彼は勢いよく話し始めた。
He started speaking with great energy.
朝の散歩で活力がわいてくる。
A morning walk gives me energy.