Phonotactic Constraints of Final Consonant Clusters in Pashto: An Analysis Based on Optimality Theory

The present article examines syllable-final consonant clusters in original and borrowed words in standard Pashto. In doing this, the phonotactic constraints on such clusters are analyzed within the framework of Optimality Theory (OT). The focus of previous research on the phonological system of Pashto has been on initial consonant clusters, however it is the belief of the authors of this article that examining the phonotactic constraints on final clusters reveals certain characteristics of the phonology of Pashto that has not been discussed before. Similarity avoidance governs final clusters of originally Pashto words; the cluster can be simplified through the deletion of a final stop in clusters in which the perceptual similarity of the members of the cluster is high. Also, the comparison of phonotactic constraints on consonant clusters of loanwords in Pashto and Persian reveals a difference in the characteristics of cluster-final nasal consonants in the two languages; while Persian tolerates violations of the Sonority Sequencing Principle (SSP), Pashto resolves loan clusters of C+n through vowel epenthesis.