The Gage Canadian Dictionary (Gage, 1997) definition of halitosis is "a disorder characterized by persistent bad or offensive breath." By bad and offensive, they mean foul smelling. Wikipedia says that the term halitosis was popularized by the makers of Listerine in about 1921, and used in advertising for their product. It stuck. Halitosis is now a common synonym for bad breath, breath odor, or oral malodor (which is, apparently, the medical term.) Well, volatile sulfur compounds - the molecules in bad breath that smell so bad - by any other name would smell just as bad, but halitosis does make it sound more like a disorder than a personal trait.

In producing a definition of halitosis, we also define the major halitosis symptom: awful smelling breath. It may also come with a tinny, sour or rotten taste in the mouth, a thick white coating on the tongue, and white patches or stones, called tonsiloliths, on the tonsils or in the tonsilar crypts. Things that cause bad breath include gum disease, sinus problems, decreased saliva production, throat infections, and a host of habits including smoking, alcohol consumption, and the enjoyment of certain foods (garlic, anyone?).

Any definition of halitosis should pay tribute to its social implications. Bad breath can indeed be so offensive that once someone gets a whiff of it, they will make sure they keep their distance from you forevermore. They may not say anything - often they don't - but they will likely take a step back and they may avert their face when you are talking. They may resort to indirect ways of telling you your breath is bad, like offering you gum or leaving a bottle of Listerine on your desk. One might consider these types of interactions as another common sort of halitosis symptom.

Although the makers of Listerine created the definition of halitosis as a marketing ploy, perhaps it was a good thing: Listerine made ingenious use of the power of language when they turned breath odor into a halitosis symptom. Bad breath is often not the fault of the person who has it, but the unfortunate result of the proliferation of a certain group of bacterial species in the airless pockets in the mouth. Giving it a name that sounds impersonal, like tonsillitis, or dermatitis, removes some of the social stigma and makes it easier for people to talk about. And it makes it sounds like something we can do something about. Never underestimate the power of a new definition of halitosis.