n. any of numerous predaceous aquatic insects of the family Notonectidae (such as Notonecta undulata) that swim on their backs and may inflict painful bites; -- also called boat bug. [ RHUD ] [ WordNet 1.5 +PJC ]
n. [ 2d back, n. + sword. ] 1. A sword with one sharp edge. [ 1913 Webster ]
2. In England, a stick with a basket handle, used in rustic amusements; also, the game in which the stick is used. Also called singlestick. Halliwell. [ 1913 Webster ]