The electromagnetic radiation produced by the acceleration of an electrically charged particle, as when an electron is deflected in the electric field of an atom or molecule.
[German : Bremse, brake (from Middle Low German premse, from pramen, to press) + Strahlung, radiation (from strahlen, to radiate, from Strahl, ray, from Middle High German strāle, from Old High German strāla, arrow, stripe; see ster-2 in the Appendix of Indo-European roots).]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.