Definition
Capacity
Capacity is the greatest amount a container can hold, often measured in millilitres or litres for liquids.
What it means
Imagine filling a container to its intended full level. The total amount it can hold is its capacity. The amount inside right now can be less than the capacity, so a half-full bottle still has the same capacity as when it is empty or full.
Remember it
Capacity asks: “How much can this container hold when full?”
Example
A bottle has a capacity of 750 mL and currently contains 300 mL. It can still hold 750 − 300 = 450 mL before reaching its full capacity.
Watch for
The 300 mL currently in the bottle is its present content, not its 750 mL capacity.
Common mix-up
A tall container does not always have greater capacity than a shorter, wider one; shape alone is not enough to decide.
Exact meaning
Capacity is the maximum amount a container can contain. In primary measurement it commonly refers to liquid capacity and is reported in units such as millilitres or litres; the container’s internal volume determines that capacity.