Line spectrum

Noun
1. a spectrum in which energy is concentrated at particular wavelengths; produced by excited atoms and ions as they fall back to a lower energy level
(hypernym) spectrum

In optics, an emission or absorption spectrum consisting of one or more narrow spectral lines, as opposed to a continuous spectrum.

A spectrum which consists solely of spectral emission lines. They are observed from luminescent gas clouds.

Compare with band spectrum and continuous spectrum .A emission spectrum that contains very sharp peaks, corresponding to transitions between states in free atoms. For example, the line spectrum of hydrogen contains 4 sharp lines in the visible part of the spectrum.