名詞 radioactivity:

1. the spontaneous emission of a stream of particles or electromagnetic rays in nuclear decay
   同義詞：radiation

1. A damaged reactor leaking radioactivity into the atmosphere.
   一座損壞的反應堆向大氣中泄露出發(fā)射性物質(zhì)
2. Russian-born American nuclear physicist known for his work on radioactivity and genetic information as well as his books popularizing theories of physics.
   伽莫夫，喬治1904－1968俄國裔的美國核物理學家，因在射線遺傳信息方面的研究和有關普及物理理論的書籍而聞名于世
3. Relating to or caused by radioactivity.
   放射產(chǎn)生的關于放射性的或由放射性引起的

ra.di.o.ac.tiv.i.ty

n.（名詞）
Spontaneous emission of radiation, either directly from unstable atomic nuclei or as a consequence of a nuclear reaction.
自動放射：自動地發(fā)出輻射，直接源于不穩(wěn)定的原子核或是作為核反應的結(jié)果
The radiation, including alpha particles, nucleons, electrons, and gamma rays, emitted by a radioactive substance.
輻射：由一種放射性物質(zhì)發(fā)出的輻射，包括α粒子、原子核、電子、和γ射線