Capacity (noun)

1. The ability or power to do, understand, or learn something.
2. The maximum amount that something can contain or produce.
3. The ability or potential to develop or improve in a particular way.

Origin:

Middle english (denoting legal competence or the ability to hold property): from old french capacité, from latin capacitas, from capax, capac- "able to hold".

Examples:

1. He has a capacity for hard work.
2. The capacity of the stadium is 100,000 people.
3. The factory has a production capacity of 50 cars per day.
4. She has a capacity for understanding difficult concepts.
5. The company is expanding its capacity to produce solar panels.