addition

noun

1.
a component that is added to something to improve it
Derived from:
add
2.
the act of adding one thing to another
Antonym:
subtraction
Derived from:
add
4.
something added to what you already have
5.
a suburban area laid out in streets and lots for a future residential area
6.
the arithmetic operation of summing; calculating the sum of two or more numbers
Derived from:
add