Ligne Joret

The Joret line (French ligne Joret) is an isogloss used in the linguistics of the langues d'oïl. Dialects north of the line have preserved Vulgar Latin /k/ and /ɡ/ before /a/; dialects south of the line have palatalized /k/ and /ɡ/ before /a/. This palatalization gave Old French /tʃ/ and /dʒ/, then modern French /ʃ/ and /ʒ/. The line was first identified by Charles Joret and published in 1883.

To the north of the line lie the Picard language and some dialects of the Norman language. To the south and the east lie other Oïl dialects including southern Norman and French. The area north of the ligne Joret is sometimes called the Normano-Picard domain.

The Joret line extends from the Channel Islands (including Jèrriais, Guernésiais and Sercquiais) and across the continent from Granville, Manche to the linguistic border with the Dutch language in the North of France and Belgium. It passes through Normandy north of Granville and Villedieu-les-Poêles and divides Manche in two linguistically and separates Calvados and Orne along with Eure.

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