Your abdomen is the middle part of the front of your body, between your chest area and your pelvis. If the doctor asks if your abdomen hurts, the doctor wants to know if you have any pain in your belly area.
The word abdomen is also the name used for the cavity, enclosed by the abdominal muscles, that contains the organs in the abdominal area. The abdomen's contents in humans include your stomach, liver, spleen, small intestine, and kidneys. The word abdomen is sometimes shortened to abs, especially in infomercials and health clubs when referring to the muscles of your abdomen and how you should want flat ones.