An exploration of vowel-pair frequencies in Lozi: implications for phonological analyses

Lozi is a Bantu language spoken predominantly in south-western Zambia. It possesses five phonemic vowel qualities and, as is common across Bantu, is noted to exhibit a form of progressive vowel height harmony. Unusually, however, Lozi lacks any alternations targeting front vowels, with only the back rounded vowels showing alternations: high [u] occurs following [i, u, e, a] but mid [o] is found after [o] itself. Furthermore, harmony is said to be limited to verb roots and following extensions, specifically reversives such as -ulul- . This paper presents a case study of vowel-pair frequencies in Lozi in both verbs and noun, where this restriction is supposedly not active, using lexicographic data. As expected based on the generalisation above, the results show that the pairs [a.o, e.o, i.o, o.u, u.o] are all highly infrequent in verbs but that [o.u] is, uniquely, also comparably infrequent in nouns. After an examination of the main data set and supplementary data, I argue this suggests that there exists in Lozi a synchronically active phonotactic restriction against this vowel pair that is blind to part of speech which applies in the non-prefixal domain, with the remaining vowel-pair gaps in verbs now being nothing more than historical residue.