Yes, it's a pun, and it's a color. More of a scale than a color. Somewhere from purplish rose to greyed grape, the universal element being a shade of purple. Sometime the word itself is included in the color name, like the "Mauve Metallic" 1966 Charger above, other times the color is given an ethereal and evocative name- as in Chevrolet's 1965 "Evening Orchid." The best name of all was probably Cadillac's "Persian Sand" of 1959.
Of course we're talking about Mauve, the purplish pinkish pastel that wormed its way into our hearts, minds, and cars beginning in the late 50s, and for ten or so stylish years appeared on our showroom floors. More sophisticated than red, cooler than blue, and always in the best of taste, we lift our hats to the many shades of Mauve: