The Roman numeral "CDLXXX" represents the number 480. In this numeral, "CD" stands for 400, "L" represents 50, and "XXX" signifies 30. When combined, these values total 480, which is a common way to express numbers in ancient Rome. Roman numerals like "CDLXXX" are part of a numeral system that originated in ancient Rome. This system uses combinations of letters from the Latin alphabet, including I, V, X, L, C, D, and M, to represent values. Roman numerals are still used today in various contexts, such as clock faces and book chapters.