The Roman numeral "CDLXXIII" represents the number 473. In the Roman numeral system, "CD" stands for 400, "LXX" represents 70, and "III" signifies 3. When combined, these values total 473. Roman numerals are a numeral system originating from ancient Rome. They use combinations of letters from the Latin alphabet, specifically I, V, X, L, C, D, and M, to signify values. This system was widely used throughout the Roman Empire and is still seen today in various contexts, such as clock faces and book chapters.