Pain is an unpleasant physical feeling that tells your body something is wrong. When you stub your toe, touch something hot, or get a splinter, pain is your body's alarm system shouting “Pay attention! Fix this!” Scientists call these signals nociceptive responses, which just means your nerves are detecting potential damage and rushing that information to your brain.

Pain comes in different forms. A sharp, sudden pain from a paper cut feels different from the dull, throbbing pain of a headache or the burning sensation of a scraped knee. Athletes sometimes describe the deep muscle pain after a hard workout, which is different from the shooting pain of an actual injury.

The word also describes emotional hurt. When a friend betrays your trust or you lose someone you love, people say it causes emotional pain because it genuinely feels like something inside you is hurting, even though there's no physical wound. Loneliness, disappointment, and grief can all be genuinely painful experiences.

As a verb, pain means to cause hurt or distress, or to feel it: “It pains me to see you left out.” We also use pain more casually. A little brother who won't stop asking questions might be called a pain, and something extremely annoying is a pain in the neck. When something requires great effort, you might say it's painstaking work, meaning it demands careful, patient attention to detail.