atom bomb
noun
- a bomb which derives its destructive power from the rapid release of nuclear energy by fission of heavy atomic nuclei, causing damage through heat, blast, and radioactivity原子弹。
Such a bomb contains a critical mass of a material such as uranium-235 or plutonium-239, which when detonated by a conventional explosive charge is capable of maintaining a nuclear chain reaction, releasing large amounts of energy almost instantaneously.