|1.||a constant value of energy in the distribution of energies among a number of atomic particles|
|2.||the energy of a quantum state of a system. The terms energy level and energy state are often used loosely to mean quantum state. This is avoided in precise communication|
One of a set of states of a physical system associated with a range of energies. Electrons in an atom, for example, can shift between the different energy levels corresponding to orbitals in different shells. Also called energy state.