When you cross the street through the middle and not at the intersections were you are supposed to. They call it Jay walking, because back in the 1900s in New York people new yorkers would call call tourist jays, and since jays were really impressed by all of the tall buildings they would walk up to the middle of the street to see how tall they were, therefore the word Jaywalking emerged

walking and smoking marijuana at the same time

to cross a street without taking advantage of provided means of safe crossing (ie crosswalks, etc.)

to walk into the street at the wrong place while motor vehicles are crossing it

Someone who crosses the street ilegaly

Crossing the street without following the crosswalk or other traffic regulations, usually on busy streets which can be hazardous.

An offensive term describing African-Americans, used by white people, when they do not want African-Americans to know they are talking about them. Term was formed in Northeast Atlanta. Probably because of African-Americans tendency to not use crosswalks when defiantly crossing busy roads.