The crossword solution for the term TON, E.G. is UNIT, a four letter word. A ton is a UNIT of measurement used to measure weight and mass. It is equal to 2, 000 pounds in the United States and 2, 240 pounds in the United Kingdom. The ton is also used to measure volume, with one ton of water being equal to approximately 908 liters. In addition, the ton is used to measure energy, with one ton of TNT being equal to 4.184 gigajoules.