spectroscopy (scientific study of spectra)

to investigate, to look up, to look into, to study, to examine, to check up on, to look over / (music) to play, to perform (an instrument) / (music) to tune

procedure; method; way; a means (to an end)

a person's nature or disposition / original characteristic of a thing; a property; a nature

importance, consequence, significance

important, significant

a spectrum

to divide light into a spectrum

material, substance

law / measure, size