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Palatal harmony, also called palatovelar harmony, is a type of vowel harmony that manifests in forcing agreement between vowels that are either neighboring or in the same word regarding their place of articulation-- specifically the difference between the palatal-articulated front vowels and the back vowels which are articulated closer to the velum. It is found in Finno-Ugric and Turkic languages, as well as the North American languages of Yawelmani and many others. Under the palatal harmony rule a word may contain either all back vowels or front vowels.