Abdominal guarding: Tensing of the abdominal wall muscles to guard inflamed organs within the abdomen from the pain of pressure upon them. The tensing is detected when the abdomen wall is pressed.

Guarding is a characteristic finding in the physical examination for an abruptly painful abdomen (an acute abdomen) with inflammation of the inner abdominal (peritoneal) surface due, for example, to appendicitis or diverticulitis. The tensed muscles of the abdominal wall automatically go into spasm to keep the tender underlying tissues from being touched.