Definition of "Complement" :
noun: something added to complete or embellish or make perfect
"A fine wine is a perfect complement to the dinner."
noun: either of two parts that mutually complete each other
noun: a word or phrase used to complete a grammatical construction
noun: number needed to make up a whole force
"A full complement of workers."
noun: a complete number or quantity
"A full complement."
noun: one of a series of enzymes in the blood serum that are part of the immune response
verb: 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."