omphalos

[om-fuh-luh s] /ˈɒm fə ləs/
noun
1.
the navel; umbilicus.
2.
the central point.
3.
Greek Antiquity. a stone in the temple of Apollo at Delphi, thought to mark the center of the earth.
Origin
1840-50; < Greek omphalós; akin to navel
British Dictionary definitions for omphalos

omphalos

/ˈɒmfəˌlɒs/
noun
1.
(in the ancient world) a sacred conical object, esp a stone. The most famous omphalos at Delphi was assumed to mark the centre of the earth
2.
the central point
3.
(literary) another word for navel
Word Origin
Greek: navel
Word Origin and History for omphalos

also omphalus, "sacred stone," 1850, from Greek omphalos, literally "navel," later also "hub" (as the central point), from PIE *ombh-alo-, from root *nobh-/*ombh- "navel" (see navel). The name of the rounded stone in the shrine at Delphi, regarded by the ancients as the center of the world. Related: Omphalic.

omphalos in Medicine

omphalos om·pha·los (ŏm'fə-lŏs', -ləs)
n. pl. om·pha·li (-lī')
The navel.