The navel (clinically known as the umbilicus, commonly known as the belly button or tummy button) is a protruding, flat, or hollowed area on the abdomen at the attachment site of the umbilical cord. All placental mammals have a navel, although it is generally more conspicuous in humans.

The navel is unique to each individual due to its being a scar, and various general forms have been classified by medical practitioners.

To minimize scarring, the navel is a recommended site of incision for various surgeries, including transgastric appendicectomy, gall bladder surgery, and the umbilicoplasty procedure itself.

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