Ancient Greek word that begins with “O” that means center/middle?

Question

I’m looking for an ancient Greek word that I think begins with “O” that means something like center or middle (my association is bellybutton). Thomas Moore uses this word in his book “Utopia”.

Answer 1

The word is omphalos (I cannot get the Greek writing to work in Yahoo Answers) and it means navel.

This is where the word "Om" comes from when meditating.

Hope this is what you wanted.

Answer 2

Meson, Mu- Used with Alpha or Omega, it symbolizes the middle...

Answer 3

its ομφαλός it means bellybutton/center of