Oar/ɔːr/ Definition 1 of 3Pro Tip 1/3Physical Action Refers to the physical effort of moving a boat with an oar. The rowers put strength into their arms as they used the oars. Pro Tip 2/3Part of Pair Oars are usually used in pairs, one on each side of the boat. Make sure both oars are securely in place before rowing. Pro Tip 3/3Rowing Sport In sports, 'oar' might indicate the activity of rowing as a competitive sport. She bought a new oar for her upcoming rowing competition.