The Chinese word "五十" is formed through a straightforward numerical composition where the character for five, "五", is directly combined with the character for ten, "十", to represent the number fifty. This follows a base-ten positional system inherent in Chinese numerals, where the first character denotes a multiplier and the second signifies the base unit, so "五" (five) and "十" (ten) together mean five tens, or fifty. This additive-multiplicative structure is a fundamental aspect of how Chinese compounds numbers, relying on the sequential placement of digits to convey value without additional grammatical markers.