The term 'bad odor' can be described by two words: 'STENCH' and 'REEK'. STENCH is a noun that refers to an unpleasant smell, usually one that is strong and offensive. It is typically used to describe a smell that is so bad it is almost unbearable. REEK is a verb that means to emit an unpleasant smell, usually one that is strong and offensive. It is often used to describe a smell that is so bad it is almost unbearable. Both words are used to describe a bad odor.