one-third
UK: wʌn ˈθɜːd | US: wʌn ˈθɜrd
n. one of three equal parts of a whole
adj. constituting or being one of three equal parts
The word "one-third" is a compound formed by combining "one" (from Old English "ān," meaning the number 1) and "third" (from Old English "þridda," meaning the ordinal form of three). The hyphenated structure reflects its function as a fractional numeral, where "one" specifies the quantity and "third" denotes the division of a whole into three equal parts. This logical pairing mirrors similar fractional terms in English (e.g., "two-thirds," "one-half").
She ate one-third of the cake before sharing the rest.
The project is one-third complete and on schedule.
Only one-third of the participants responded to the survey.
The recipe calls for one-third cup of sugar.
His salary increased by one-third after the promotion.