what is a megaton bomb
Noun. 1. megaton bomb-a nuclear weapon with an explosive power equivalent to one million tons of TNT. bomb-an explosive device fused to explode under specific conditions. atomic weapon, nuclear weapon-a weapon of mass destruction whose explosive power derives from a nuclear reaction.1  Facebook.oun. 1. megaton bomb-a nuclear weapon with an explosive power equivalent to one million tons of TNT. bomb-an explosive device fused to explode under specific conditions. atomic weapon, nuclear weapon-a weapon of mass destruction whose explosive power derives from a nuclear reaction.