OWI stands for Operating While Intoxicated or Operating While Impaired, and it is a term used in some states in the United States to describe the crime of drunk driving instead of the more common DUI terminology. OWI and DUI are acronyms used interchangeably to describe drunk driving offenses in different states, and they both refer to the same type of offenses with similar penalties. In some states, OWI casts a wider net than simply driving while under the influence, and it is also illegal to operate a motor vehicle with its engine running, regardless of motion.