|the characteristic pattern of dark lines or bands that occurs when electromagnetic radiation is passed through an absorbing medium into a spectroscope. An equivalent pattern occurs as coloured lines or bands in the emission spectrum of that medium|
absorption spectrum n.
The electromagnetic spectrum, broken by a specific pattern of dark lines or bands, observed when radiation traverses a particular absorbing medium.
The range of frequencies of electromagnetic radiation readily absorbed by a substance by virtue of its chemical composition. See more at atomic spectrum.