CEFR C1

absorption feature

noun phrase

Meaning

A dip in a spectrum of light or other radiation that occurs when a substance absorbs specific wavelengths, revealing the chemical composition of the absorbing material.

Examples

  • Astronomers identified a prominent absorption feature in the spectrum of the distant galaxy.
  • The material's unique absorption feature allowed scientists to determine its molecular structure.

Synonyms: absorption band, spectral line, absorption spectrum