Tongue-Root Harmony [Atr]/[Rtr]

Abstract This chapter’s primary focus is on describing major patterns and aspects of typological variation associated with tongue-root harmony systems in African languages. Vowel harmony systems based on a tongue-root feature called advanced tongue root [ATR] occur widely in the Niger-Congo and Nilo-Saharan phyla of Sub-Saharan Africa. Outside Africa, tongue-root harmony systems have been identified in various other regions and phyla, though not always without controversy. The chapter itemizes the more common vowel inventories in which tongue-root harmony typically occurs, illustrates harmony in its most complete and symmetric form, and discusses widespread asymmetries and complexities that occur, including directional asymmetries and variation in the scope of the harmony domain, asymmetries related to the patterning of phonemically unpaired vowels, and asymmetric dominance or spreading of particular [ATR] values. A brief partial sampling of cases of tongue-root harmony outside Africa, with references to more extensive discussion elsewhere, is included in the final section.