A Roadcone is a penis shaped similar to a constructiontraffic cone. Narrow tip or head that widens to a girthy shaft base. It is the opposite of a bulbous penis.
When Joe dropped his pants, his new girlfriend was shocked by his Roadcone that stood before her.
when you get a boner driving down the highway due to road vibrations. usually starts when thinking about sex coupled with big bump in road. can be quite annoying