General Definition: 1. Any large long horizontal cylindrical object, such as a log or tree trunk, or any thing or action directly or indirectly associated with this, especially a pipe or tube. As a Noun: 1. A shape or an object with flat circular ends and long straight sides. English = cylinder. 2. A long, narrow, round, hollow object, usually made of metal or plastic, through which a liquid or gas can flow. English = pipe, tube.