(physics) a hydrogen-like system consisting of an ordinary nucleus with a hadron in orbit.

Alternative form of atomizer

On the top of. / On the top, with "of".

(literary or archaic) On, to, or at the top.

plural of atomus

(physics) an early nuclear reactor fuelled by uranium and moderated with graphite

The era, starting in the mid-1940s, during which nuclear energy was developed, and in which it was thought that all energy would be provided by such sources.

(physics, chemistry) the equivalent of an atom in which either the nucleus, or an electron, is replaced by some other subatomic particle

(physics) any device that converts the energy of particles emitted from atomic nuclei into electrical energy

(uncountable) The quality or state of being atomic. / (chemistry) The number of atoms in a molecule.