low-energy rule
noun phraseUK /ˌləʊ ˈɛnədʒi ruːl/
US /ˌloʊ ˈɛnərdʒi ruːl/
A low-energy rule is a rule that says you should not use too much energy.
The school made a low-energy rule to turn off the lights when nobody is in the room.
RELATED WORDS
OTHER MEANINGS
2. A rule in a game or sport that limits how much energy a player can use.
The low-energy rule in the race meant players could only walk, not run.
3. A guideline in a building that asks people to use less electricity.
The office follows a low-energy rule by keeping the heat low in winter.
4. A simple rule that keeps something running without using much power.
The robot follows a low-energy rule to save its battery.