Do you think you know all the lexicom for the auto shapes? But do you know how to talk like a designer? For example dashboard in the designer's language is I.P. I am sure this you didn't knew.

Dropping in a mention of the greenhouse or the beltline is pretty easy, but you will really get points with casual references to A-, B-, and C-pillars, the order of the roof supports arranged from the windshield, whose base is called the cowl, to the rear window, or backlight. You might say, “That fat C-pillar would make it impossible to parallel park.”

The beltline divides the greenhouse, or glassed-in upper body, from the portion that extends down from the window sills. Equally important is the A-line, said Michael Castiglione, principal exterior designer at DaimlerChrysler’s Pacifica studio in Carlsbad, Calif. The A-line runs the length of the body from headlight to taillight, tracing the car’s silhouette. The car may also have a character line, a crease formed in the sheet metal of the sides.

The body section below the base of the door, or rocker panel, is treated with a varying degree of turn-under, which Chris Chapman of BMW’s Designworks studio in Newbury Park, Calif., defines as the shape of the panel as it curves inward at the lower edge. The front face of a car is visually grounded in the lower fascia or valance, typically made of plastic these days.

One critical element, designers said, is the axle-to-dash ratio, the proportion between the front wheel and the cowl (which is the base of the windshield). It helps to define the visual personality of the car.

There is also what is called the roller skate effect, where the wheels and tires are too small for the body. (Volkswagens of the 1980s seemed to have especially small wheels proportionally, and fell prey to this phenomenon.) Huge wheels of 20, 22 or 23 inches, by contrast, make a vehicle look tough.

The space between wheel and surrounding fender or wheel well suggests the jounce of the car. The intervening space between tire and wheel well is sometimes called the dead cat hole, according to Peter Davis, director of interior design for global compact utility vehicles at G.M.

Companies have their own phrase books. At BMW, a crease or body line on the side of a car is a zicke, Mr. Chapman said. For New Yorkers, Mr. Chapman noted that the often-used Hofmeister Knick, referring to the traditional dogleg shape at the base of the C-pillar of BMWs, “is pronounced ka-nic, not like the basketball team.”