belly button 
noun informal
A person’s navel.Squeeze your buttocks, draw your belly button to your spine and tilt your pelvis....
- She is nude and the image shows her body from her belly button to her knees.
- Most want ear or nose piercings, although a few prefer to have their belly button or genitals pierced.
- go down the plughole
- go down the toilet
- go down the tube (or tubes)
- go down the wrong way
- go down with
- godpapa
- godparent
- God particle
- Godpenny
- godpoppa
- God's acre
- God's ape
- God Save the Queen
- God's book
- God's chest
- God's church
- God's cope
- God's country
- God's creatures
- God's day
- God's earth
- Godself
- godsend
- God's-eye view
- God's gift