Grimm's law is a linguistic rule that describes the systematic sound alterations that have happened throughout the history of Germanic languages. It was developed by German philologist Jacob Grimm in the early nineteenth century. The law clarifies the relationships between specific consonant sounds in Germanic languages and their counterparts in other Indo-European languages.
Grimm's law is a key notion in historical linguistics, having had a considerable impact on our understanding of language evolution and the links across language families.
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