Kit–bit split

The kit-bit split is a split of EME /ɪ/ found in South African English, where kit [kɪt] and bit [bət] do not rhyme. It is not clear whether this is a true phonemic split, since the distribution of the two sounds is predictable: [ɪ] is used adjacent to velars (kiss, gift, lick, big, sing, kit), after /h/ (hit), word-initially (inn), generally before /ʃ/ (fish), and by some speakers before /tʃ, dʒ/; [ə] is used elsewhere (limb, dinner, limited, bit). Nevertheless because of the phonetic similarity of the two vowels in a word like dinner [ˈdənə], Wells argues that they belong to the same phoneme /ə/, while the vowel of kiss, big, hit, inn etc. belongs to the phoneme /ɪ/. The kit-bit split is perhaps the most distinctive feature of South African English, as many of its other features are also found in New Zealand English.

Centralized realizations of the vowel in bit is also found in New Zealand English. Unlike in South African English, bit and kit rhyme as /bət/ and /kət/ in New Zealand English, since it doesn't involve a split.

References

^ http://www.hi.is/~peturk/KENNSLA/87/VARS/KITetc.htm
^ Wells, op.cit., pp. 612–13