ˌəmˈbilə̇kəs, -ˈbilēk- also ˌəmbəˈlīkəs noun
( plural umbili·ci ˌ ̷ ̷ˈ ̷ ̷ ̷ ̷ˌkī, -ˌsī, -ˌkē; ˌ ̷ ̷ ̷ ̷ˈ ̷ ̷ˌkī, -ˌsī ; or umbilicuses )
Etymology: Latin — more at navel
1.
a. : a small depression in the middle of the abdomen where the umbilical cord is attached in the embryo
b. : the place where the extraembryonic structures are continuous with those of the body proper of the embryo
2. : a cavity in the center of the base of a spiral shell that is surrounded by the whorls
3.
a. : hilum
b. : a rootlike attachment of the thallus in a lichen
4. : a central point : core , heart
the key to control, the umbilicus of this … sea — J.P.O'Donnell