Meaning of omega-minus particle

o•me'ga-mi'nus par"ticle

Pronunciation: (ō-mē'gu-mī'nus, -mā'-, ō-meg'u-), [key]
— Physics. Physics.
  1. a baryon with strangeness −3, isotopic spin 0, and negative charge; predicted from the mathematics of the Eightfold Way and subsequently discovered. Symbol: &OHgr;
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.