Colic is severe stomach or belly pain that comes in waves, making a person (or animal) cry out or curl up in discomfort. The word most often describes the mysterious, intense crying episodes that affect some babies during their first few months of life. A baby with colic might cry for hours, especially in the evening, even though they're fed, dry, and nothing seems obviously wrong. Parents of colicky babies often feel exhausted and worried because nothing they try seems to help much.

Doctors aren't entirely sure what causes infant colic, though it usually disappears on its own after a few months as the baby's digestive system matures. The word can also describe stomach pain in older children and adults, particularly sharp, cramping pain that comes and goes rather than hurting constantly. Horses can get colic too, which is serious because their digestive systems are delicate.

The term colicky describes someone experiencing this type of pain. While colic is miserable while it lasts, it usually doesn't cause lasting harm and eventually passes, which can give struggling parents hope during those long crying nights.