A compliment is an expression of respect or admiration, like, "You're such a good writer," or "You know so many words!" Keep them coming.
Compliments are always welcome, because they usually make people feel good. It’s saying something nice about someone or something. If you get mysterious flowers, look at the card – perhaps it will say “compliments of your upstairs neighbors,” as an apology for playing their music too loud all night. Or if you say, “my compliments to the chef!” you really liked your meal.