the size of a ship or the amount it can carry, expressed in tons （表示船舶大小或载重量的）吨位 the total amount that something weighs （某物的）总重量 the total tonnage of bombs dropped in the war 战争中投下的炸弹总吨位
Word Originearly 17th cent. (denoting a charge per ton on cargo): from ton + -age.