The speech-feature definition of a component may vary over different parts of its length. E.g. if ¯ extends over all successive consonants, it is defined as representing voicelessness only over what we may call stops and aspirants. When it extends over a cluster which includes /r, l, m, n, w, y/, it is defined as indicating zero (i.e. no phonemic difference) over those phonemes: if we write /zdrey/ for 'stray' and /drey/ for 'dray', we have /r/ = /r/ whereas /d/ does not equal /d/.
- Harris (1951), a pag.129