Sickness is the state of being ill or unhealthy, when your body isn't working the way it should. When you wake up with a fever, sore throat, and stuffy nose, you have a sickness. Doctors might call it an illness or disease, but sickness is the everyday word we use when something's wrong with our bodies.

Sickness comes in many forms. Some sicknesses, like the common cold or flu, go away after a few days of rest. Others, like diabetes or asthma, are chronic, meaning they last a long time and require ongoing treatment. Some sicknesses spread easily from person to person (that's why you cover your mouth when you cough), while others can't be caught from someone else.

The word can also describe a queasy, upset feeling in your stomach. Motion sickness happens when the movement of a car or boat makes you feel nauseated. You might feel a wave of sickness before vomiting.

People sometimes use “sickness” more broadly to describe problems in society or organizations, like talking about the sickness of corruption in a government. This metaphorical use suggests something unhealthy that needs fixing, just like a body needs healing when it's sick.