spectrometer

n. instrument for measuring spectral wave lengths

A spectrometer is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization state. The independent variable is usually the wavelength of the light, normally expressed as some fraction of a meter, but sometimes expressed as some unit directly proportional to the photon energy, such as wavenumber or electron volts, which has a reciprocal relationship to wavelength. A spectrometer is used in spectroscopy for producing spectral lines and measuring their wavelengths and intensities. Spectrometer is a term that is applied to instruments that operate over a very wide range of wavelengths, from gamma rays and X-rays into the far infrared.
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Spec·trom·e·ter n. A spectroscope equipped with scales for measuring wavelengths or indexes of refraction. spec tro·met ric adj. [more]Spectrometer - Community and Resources

Noun
1. spectroscope for obtaining a mass spectrum by deflecting ions into a thin slit and measuring the ion current with an electrometer
(synonym) mass spectrometer
(hypernym) spectroscope, prism spectroscope
(hyponym) mass spectrograph

n. spectrometer