Frequency effects and lexical split in the use of [t] and [s] and [d] and [z] in the Syrian Arabic of Christian rural migrants

The change of the Standard Arabic interdentals, [θ] > [t] and [s], and [ð] > [d] and [z], in some Egyptian and Levantine Arabic dialects was traditionally explained in terms of two historical changes. The first change was a complete merger of [θ] with [t] and [ð] with [d]. The second change, i.e. [θ] > [s] and [ð] > [z], began with borrowing words with [θ] and [ð] from Standard Arabic, replacing them with similar sounds from speakers’ native phonology — [s] and [z] respectively. The data set used in this study comprises of naturally occurring speech of fifty-two Christian rural migrants to the city of Hims in Syria. The findings suggest that there is no variation in the use of [t] and [s] instead of [θ]. There is rather a synchronic puzzling STABLE LEXICAL SPLIT PHENOMENON: some words are specifically used with [t] and others are specifically used with [s]. The same applies to [d] and [z]. The study shows that although the two historical changes play a role, they are not the sole explanation of this stable lexical split phenomenon. Hence, the role of frequency is examined. Quantitative analyses reveal that highly frequent words are produced with the stops, whereas less frequent words are produced with the fricatives. This phenomenon is explained in terms of usage-based theory and two opposing frequency effects. The first frequency effect led to the merger with the stops. The second frequency effect made highly frequent words produced with the stops resistant to the second change that introduced words with the fricatives.