addition

Something added to what you already have.

“he was a new addition to the staff”

A component that is added to something to improve it.

“the addition of a bathroom was a major improvement”

“the addition of cinnamon improved the flavor”

A quantity that is added.

“there was an addition to property taxes this year”

The arithmetic operation of summing; calculating the sum of two or more numbers.

A suburban area laid out in streets and lots for a future residential area.

The act of adding one thing to another.

“the addition of flowers created a pleasing effect”

“the addition of a leap day every four years”