Phonological change of vowel length in Farsi

There are six vowels in the modern Farsi. Generally it is claimed that vowel length is not a phonemic characteristic in this language. On the other hand, many of the researchers show that the deletion of glottal consonants in the coda cluster is followed by a compensatory lengthening in Farsi. The purpose of this paper is to analyze minimal pairs having contrast only in vowel length. Forty words were collected for this purpose. These words are arranged into monosyllables minimal pairs. It's argued that glottal consonants are analogically deleted in coda. This phonetic process causes vowel lengthening. Hereby, many words are equally except of their vowel length. This leads to the existence of minimal pairs with different vowel length. Conclusion is that vowels are under progressing change and probably vowel length will be one of the phonemic features of the vowels in Farsi. Keywords: Farsi vowels, vowel length, Compensatory lengthening