noun eta·lon \ˈātəlˌän, ˈet-\

Definition of etalon



  1. :  an interferometer in which two parallel partially silvered glass plates at a fixed distance apart produce by multiple reflection interference spectra of high dispersion and resolution adapted to the fine-structure analysis of spectrum lines

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Origin and Etymology of etalon

French étalon standard of weights and measures, from Middle French estalon, estelon, probably of Germanic origin; akin to Frisian stal shape, form

Seen and Heard

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to cast off or become cast off

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