Unwell means sick or not feeling healthy. When you're unwell, you might have a headache, upset stomach, sore throat, or just feel weak and tired. Your body is telling you something isn't right.

People use unwell as a polite or formal way to say “sick.” A teacher might tell the class that a student is unwell and staying home today. A doctor's note might say a patient is feeling unwell and needs rest. It can sound more dignified than saying someone is “sick” or “ill,” though all three words mean essentially the same thing.

Sometimes people say they feel generally unwell when they can't point to one specific problem, they just don't feel like themselves. Maybe they're achy, tired, and a bit dizzy all at once. The word captures that overall sense of not being right without having to list every symptom.

You might also hear unwell used more broadly to suggest someone is troubled or upset, though this usage is less common. When someone says “I felt quite unwell about the whole situation,” they mean it bothered or distressed them. But usually, unwell simply means your body needs rest and care to get back to normal.