Accumulator (noun)

1. A device or system that stores energy, especially electricity.
2. A person or entity that accumulates or collects things over time.

Origin:

Derived from the latin word "accumulare" which means "to pile up".

Examples:

1. The wind turbine has an accumulator that stores excess energy for later use.
2. The batteries in the car serve as the primary accumulator for electrical energy.
3. He was a known accumulator of antique cars and had a vast collection.
4. The company's stock portfolio serves as an accumulator of wealth for the firm.
5. She was a lifelong accumulator of rare books and had a library that was the envy of many collectors.