spectroscopy
Concise Oxford English Dictionary © 2008 Oxford University Press:
spectroscopy/spekˈtrɒskəpi/
▶noun the branch of science concerned with the investigation and measurement of spectra produced when matter interacts with or emits electromagnetic radiation.
– derivatives
spectroscopic adjective,
spectroscopically adverb,
spectroscopist noun.
spectroscopic adjective,
spectroscopically adverb,
spectroscopist noun.
'spectroscopy' also found in these Oxford entries:

