'non-spectroscopic' originates from the prefix 'non-' (from Latin 'non', meaning 'not') combined with 'spectroscopic', which itself derives from Neo-Latin and English formations based on Latin 'spectrum' and Greek 'skopein' (to look).

'spectroscopic' developed in the 19th century from 'spectroscope' (coined from Latin 'spectrum' and Greek 'skopein'), became the adjective 'spectroscopic', and the modern formation 'non-spectroscopic' arose by adding the negative prefix 'non-'.

Initially it meant 'not related to the use of a spectroscope'; over time the sense has remained but broadened to include 'not detectable or analyzable by spectroscopic methods.'