Entry 1 sense Webster, 1913 Ulster /ŭl'-stẽr/ · Ul·ster · IPA /ˈʌlstɚ/ 01 n. A long, loose overcoat, worn by men and women, originally made of frieze from Ulster, Ireland. 1. A long, loose overcoat, worn by men and women, originally made of frieze from Ulster, Ireland.