Grimm's law

noun Linguistics.
  1. the statement of the regular pattern of consonant correspondences presumed to represent changes from Proto-Indo-European to Germanic, according to which voiced aspirated stops became voiced obstruents, voiced unaspirated stops became unvoiced stops, and unvoiced stops became unvoiced fricatives: first formulated in 1820–22 by Jakob Grimm, though the facts had been noted earlier by Rasmus Rask.
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British Dictionary definitions for grimm's law

Grimm's law

noun
  1. the rules accounting for systematic correspondences between consonants in the Germanic languages and consonants in other Indo-European languages; it states that Proto-Indo-European voiced aspirated stops, voiced unaspirated stops, and voiceless stops became voiced unaspirated stops, voiceless stops, and voiceless fricatives respectively

Word Origin for Grimm's law

formulated by Jakob Grimm
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