Grimm's law

Grimm's law (also known as the First Germanic Sound Shift or Rask's rule) is a set of statements named after Jacob Grimm and Rasmus Rask describing the Proto-Indo-European (PIE) stop consonants as they developed in Proto-Germanic (the common ancestor of the Germanic branch of the Indo-European family) in the 1st millennium BC. It establishes a set of regular correspondences between early Germanic stops and fricatives and the stop consonants of certain other centum Indo-European languages (Grimm used mostly Latin and Greek for illustration).


Grimm's law was the first discovery of a systematic sound change, and it led to the creation of historical phonology as a separate discipline of historical linguistics. The correspondence between Latin p and Germanic f was first noted by Friedrich von Schlegel in 1806. In 1818, Rasmus Rask extended the correspondences to other Indo-European languages such as Sanskrit and Greek, and to the full range of consonants involved. In 1822, Jacob Grimm put forth the rule in his book Deutsche Grammatik and extended it to include standard German. He noticed that there were many words which had different consonants from what his law predicted, and these exceptions defied linguists for a few decades, but they eventually received explanation from Danish linguist Karl Verner in the form of Verner's law.

Other Languages
aragonés: Lei de Grimm
asturianu: Llei de Grimm
български: Закон на Грим
català: Llei de Grimm
čeština: Grimmův zákon
español: Ley de Grimm
Esperanto: Leĝo de Grimm
estremeñu: Lei de Grimm
français: Loi de Grimm
galego: Lei de Grimm
한국어: 그림의 법칙
Bahasa Indonesia: Hukum Grimm
italiano: Legge di Grimm
עברית: חוק גרים
қазақша: Гримм заңы
lietuvių: Grimo dėsnis
Lingua Franca Nova: Lege de Grimm
lumbaart: Leg de Grimm
norsk: Grimms lov
polski: Prawo Grimma
português: Lei de Grimm
română: Legea lui Grimm
русский: Закон Гримма
slovenščina: Grimmov zakon
svenska: Grimms lag
українська: Ґріммів закон
中文: 格林定律