The conceptual position of the vowel /a/ in Turkish in the context of the phonetic-phonological continuum and the vowel quadrilateral

This study aims to determine the position of the Turkish vowel /a/ within the vowel quadrilateral and to identify the most appropriate International Phonetic Alphabet (IPA) symbol for representing it at the phonemic level. In addition, by exemplifying the sub-phonemic variations of /a/ in Turkish, the paper discusses how the boundary between the phonetic and phonological levels can be more accurately defined from a theoretical perspective. The historical background of the transition from the articulatory triangle model to the acoustic quadrilateral model is summarized, and the conceptual confusion arising from the misinterpretation of phonetic representations as phonological explanations is examined. The concept of the phonetic–phonological continuum is addressed as a key factor underlying the frequent conflation of these two domains. Interpreting the phonological properties of phonemes solely on the basis of phonetic data represents a major consequence of this conceptual ambiguity. However, phonological properties should be established not through physical measurement but through abstraction. In this regard, perceptual phonetic studies and the contemporary phonological framework known as Element Theory may offer a more consistent means of defining phonological categories. In conclusion, the essential phonological property of the Turkish /a/ vowel is its openness (vowel height), while its backness or frontness belongs to the phonetic plane; therefore, it should be represented at the phonemic level with the symbol /a/.

 Keywords: Phonetics, Phonology, Vowel quadrilateral, Turkish