umbilicus

US /ʌmˈbɪl.ə.kəs/
UK /ʌmˈbɪl.ə.kəs/
1.

lỗ rốn

the small, round part in the middle of the belly that is left after the umbilical cord (= the long tube of flesh joining the baby to its mother) has been cut at birth:

:
Unlike other mammals, the human umbilicus is clearly visible.