reservepower
nounUK /rɪˈzɜːv ˌpaʊə/
US /rɪˈzɜːrv ˌpaʊər/
Extra power that is kept ready to use when it is needed.
The hospital has reserve power so the lights stay on during a storm.
RELATED WORDS
OTHER MEANINGS
2. The ability to stay calm and strong for later use.
She kept some reserve power for the last lap of the race.
3. Extra strength a machine or engine keeps in case of heavy work.
The truck's reserve power helped it climb the steep hill.
4. Power held back by a country or army for emergencies.
The general kept reserve power ready in case the battle changed.