Compliment vs Complement
‘Complement’ and ‘compliment’ are sometimes confused because they are pronounced the same and have very similar spellings. Both function as noun and verb, but are quite distinct in meaning.
As a noun, ‘compliment’ refers to an expression of esteem, admiration or praise. For example, to call someone handsome/beautiful is to pay him/her a compliment, and the verb refers to this action, ie, the paying of a compliment.
On the other hand, as a noun, the ‘complement’ of something supplies what that something is missing, ie, completes or perfects it. For example, wine can be said to complement a meal.