a dirty navel
Well, sweetheart, your belly button is called a belly button because it's literally a button-like scar left behind from where your umbilical cord was attached during fetal development. It's not winning any creativity awards, but hey, at least it's descriptive and to the point.
Yes. "Belly button" is another name for a person's naval.
a dirty navel
Abdomen
He was rumored to not have a belly button.
Anti-navel
umbilical area
Umbillical Cord
Your navel
I don't know what you mean by "undo" your belly button but you can get what is called an "umbillical hernia" inside near your belly button.
because it has a bell y button shape!
Out Belly Button