Published online by Cambridge University Press: 01 January 2026
We propose that contour nasals come from two principal sources. One source, articulatorily driven, comes from underlying voiced stops, as nasal venting in order to sustain voicing. The other, perceptually driven, comes from underlying nasal consonants, as shielding next to contrastively oral vowels. Although both processes are phonetically well motivated, we argue that the contoured allophones specifically arise in languages in which systemic or phonotactic restrictions allow for easy recoverability of the corresponding underlying segment. Finally, we present a few cases of contour nasals in preconsonantal contexts that seem to be neither venting nor shielding, and suggest that these arise due to place-of-articulation enhancement in clusters. We offer diagnostics for distinguishing nasal venting from shielding and present case studies from South American languages in which understanding such phenomena as enhancement involves analytical commitments to what is contrastive in the language.
Thanks to Selmo Apontes, Claudine Chamoreau, Natacha Chevrier, Megan Crowhurst, Matt Gordon, Larry Hyman, An Van linden, Monica Macaulay, Alexis Michaud, Andrey Nikulin, Maria-Josep Solé, Bert Vaux, and especially to two Language referees for useful discussion. Special thanks go to Dany Mahecha for discussion and recordings of the Nikak data, to Marcia Nascimento Kaingang for discussion and recordings of the Kaingang data, and to Rui Rothe Neves and Ronaldo Lima Jr. for discussion and assistance with acoustic analyses of prevoicing, prenasalization, and prevocalization.