sesquioxide: Meaning and Definition of

ses•qui•ox•ide

Pronunciation: (ses"kwē-ok'sīd, -sid), [key]
— n. Chem.
  1. an oxide containing three atoms of oxygen and two of another element, as aluminum oxide, AlO.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.