The Canadian Oxford Dictionary defines perpendicular as being “at right angles (to a given line, plane, or surface). With this style of parking, drivers move their vehicles into position side by side, often pulled up with one end facing a curb or the side of a building. Here, the term “perpendicular” refers to the position of the vehicle in relation to the line or surface. Sometimes, vehicles park against a curb or other barrier, while at other times, the spaces are marked only by lines on the pavement.