A member of the crew is someone who works on a boat or ship, and there are several different roles they can take. A SAILOR is someone who operates and maintains a vessel, and they are typically responsible for navigation and other duties. An OAR is a long pole with a flat blade at one end used to propel a boat through the water, and a ROWER is someone who uses oars to move a boat. An OARSMAN is someone who rows a boat using oars.