Somebody who can be asked how to get somewhere on the road and not even have to think about it before responding with an answer and can name other major cities on the route. Also have everyday thoughts influenced by driving and going places.
Guy: Hey Roadgeek, how do I get from Duluth, Minnesota, to Laredo, Texas?
Roadgeek: Take Interstate 35 south through Minneapolis/St. Paul, Des Moines, Kansas City, Wichita, Oklahoma City, Dallas/Ft. Worth, and San Antonio and you will get there.
Person inordinately fascinated with some or all aspects of highways, including history, construction, numbering, and roadtripping.
For roadgeeks in the San Francisco area, I-238 is a must-visit destination.