complement

Something added to complete or embellish or make perfect.

“a fine wine is a perfect complement to the dinner”

Number needed to make up a whole force.

“a full complement of workers”

A complete number or quantity.

“a full complement”

A word or phrase used to complete a grammatical construction.

Either of two parts that mutually complete each other.

One of a series of enzymes in the blood serum that are part of the immune response.

Make complete or perfect; supply what is wanting or form the complement to.

“I need some pepper to complement the sweet touch in the soup”