A cross between a dick, cock, and penis. When you don't know which to say to a girl, you combine them all. Dockis is the truescientific name for a dick, cock or penis. They are usually 1 - 24 inches in length, and come in many colors.
Boy: Hey would you wanna suck my dockis after school sometime?
The act of modifying a vehicle to fit a much larger wheel and tire package on a car than it was originally designed for, usually making it look monster-truckish.