Oar Wooden Sword (櫂の木刀?) is a Noble Phantasm possessed by the male Miyamoto Musashi from the Greater History of Man. Despite being listed in the female Musashi's profile, she does not possess this Noble Phantasm. It is the wooden sword said to be used in the battle against Sasaki Kojirou.
Some sources about the battle state Musashi used a dual-weilding style with two wooden swords, one measuring 95cm and the other measuring 106cm. Other sources say it was single sword measuring over two meters in length, which surpasses the length of Sasaki's Monohoshi Zao. There is a theory that the wooden sword was not chosen as a clever scheme to defeat Koujirou or attempt to overcome the length of Monohoshi Zao, but rather that he was already proficient with it and was just using a weapon with which he was familiar to ensure victory.