A complainer is someone who frequently points out problems, expresses dissatisfaction, or voices grievances about things that bother them. When someone complains constantly about homework, the weather, their lunch, and the rules at recess, they've earned the label of being a complainer.

There's an important difference between complaining and constructively pointing out genuine problems. If the cafeteria serves spoiled milk, telling a teacher isn't complaining: it's identifying a real issue that needs fixing. But a complainer focuses on minor annoyances and keeps expressing unhappiness without trying to improve the situation or accept things they can't change.

Complainers often don't realize how their constant negativity affects others. When someone grumbles about everything, friends and classmates start tuning them out, even when they might have a valid point. The kid who complains about every assigned book might have legitimate criticisms about one of them, but nobody takes him seriously anymore.

The opposite of a complainer isn't someone who never notices problems. It's someone who distinguishes between things worth addressing and things worth accepting, and who looks for solutions rather than just dwelling on what's wrong. Nobody enjoys spending time with a chronic complainer, someone whose default response to life is finding fault and expressing discontent.