om·pha·los (ŏmfə-lŏs′, -ləs)
n. pl. om·pha·li (-lī)
1. The navel.
2. A central part; a focal point.
3. Any of various stones revered as sacred in ancient Greek civilization, representing the center of the world.
[Greek; see nobh- in the Appendix of Indo-European roots.]
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