halitosis UK /hæl.ɪˈtəʊ.sɪs/US /hæl.ɪˈtoʊ.sɪs/ noun1 •The condition of having stale or foul-smelling breath.Bad breath or halitosis is an indication of a disturbed digestive system. It is indicative of a bowel toxemia in either the small or large intestine with an overgrowth of bacteria or yeast. — 2004 formshalitoses