The term 'Motor City Monogram' is a reference to the city of Detroit, Michigan, which is known as the Motor City due to its long history of automobile production. The two crossword solutions for this term are REO and UAW. REO stands for the REO Motor Company, which was founded in 1904 and was one of the first companies to mass-produce automobiles. UAW stands for the United Auto Workers, which is a labor union that was founded in 1935 and has been representing workers in the automotive industry ever since.