1. A measure of explosive power (of an atomic weapon) equal to that of one million tons of tnt.
2. One million tons.
Measure of explosive force of atomic and hydrogen bombs, equal to that of 1 million tons of T.N.T.
One million (106) tons. Used with reference to the explosive power of a nuclear weapon, it is equivalent to the explosive force of one million tons of trinitrotoluene (TNT).