Word Study
fraunhofer lines
CIDE DICTIONARY
fraunhofer lines, prop. n. pl.
The lines of the spectrum; especially and properly, the dark lines of the solar spectrum, so called because first accurately observed and interpreted by Fraunhofer , a German physicist. [1913 Webster]
OXFORD DICTIONARY
fraunhofer lines, n.pl. the dark lines visible in solar and stellar spectra.
Etymology
J. von Fraunhofer, Bavarian physicist d. 1826
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