The
navel (clinically known as the
umbilicus, colloquially known as the
belly button, or
tummy button) is a
scar on the
abdomen at the attachment site of the
umbilical cord. All
placental mammals have a navel, and it is quite conspicuous in humans. Other animals' navels tend to be smoother and flatter, often nothing more than a thin line, and are often obscured by fur.