plus fours
noun /ˌplʌs ˈfɔːz/
  /ˌplʌs ˈfɔːrz/
[plural] (British English)- wide loose trousers that end just below the knees, where they fit closely, and that used to be worn, for example, by men playing golf - a pair of plus fours
 Word Origin1920s: so named because the overhang at the knee required an extra four inches of material.