The medical term for bad breath is halitosis. It is a condition characterized by unpleasant odors emanating from the mouth due to various underlying causes such as poor oral hygiene, dry mouth, gum disease, cavities, and other health conditions. In some cases, halitosis may indicate a more serious underlying condition such as respiratory infections, liver or kidney problems, or diabetes. Treatment may include addressing the underlying cause, improving oral hygiene, and using mouthwashes or medications to freshen breath.