Energizer (noun)

1. A device or substance that supplies energy or increases the energy level.
2. A brand of batteries.

Origin:

From the verb "energize" which comes from the latin word "energia" meaning energy.

Examples:

1. The athlete drank an energizer before the race to boost his energy.
2. The energizer kept the flashlight running for hours.
3. The company developed a new energizer that is more efficient than the previous version.
4. The party was an energizer and lifted everyone's spirits.
5. I always carry an Energizer brand battery in my emergency kit.