The Collaborative International Dictionary
Omo- \O"mo-\ [Gr. ? the shoulder.] A combining form used in anatomy to indicate connection with, or relation to, the shoulder or the scapula.
Douglas Harper's Etymology Dictionary
before vowels om-, word-forming element meaning "raw, unripe," from Greek omo-, comb. form of omos "raw," from PIE root *om- "raw, sharp-tasting" (cognates: Sanskrit amah "raw, uncooked, unripe," Old Irish om, Welsh of).
pre. (context anatomy English) of the shoulder or scapula