Rydah is basically a slang word for Rider. It sounds much more dope and is usually used by rappers and gangsters. The word is said to originated from the West Coast of the United States, somewhere along the Bay Area.
Rydah is a term used for an uneducated, racist person. Usually found in the KC, MO area of the U.S. An individual warranting this name will probably be accompanied by violent behavior, ebonics and poor fashion sense.