BOATER Meaning of BOATER in English boat ‧ er /ˈbəʊtə $ ˈboʊtər/ BrE AmE noun [countable] [ Date: 1800-1900 ; Origin: Because it was originally used for boating ]a hard ↑ straw hat with a flat top Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012