a device that measures time extremely accurately using the vibrations (= fast, regular small movements) of atoms

The atomic clock is so precise it shouldn't lose or gain a second in 20 to 30 billion years. 原子钟非常精确，在200到300亿年内不会丢失或增加一秒。

His discovery of the magnetic properties of atoms gave rise to superaccurate atomic clocks. 他对原子磁性的发现催生了超精确原子钟的发明。