The use of spectroscopes to analyze spectra WordNet 3.0 & Open English WordNet

Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Wikipedia

Interaction between matter and electromagnetic radiation broken down into frequencies Wikidata

The branch of physics concerned with the production, measurement, and interpretation of electromagnetic spectra arising from either emission or absorption of radiant energy by various substances. OmegaWiki

The measurement of the wavelength of electromagnetic radiation, especially any of several techniques used to analyze the structure of molecules; the measurement of spectra of things other than radiation, such as the masses of molecules and their breakdown products. Wiktionary

Measurement of the wavelength of electromagnetic radiation. Wiktionary (translation)