摘要:Dissimilation is classically considered as a phonetically categorical sound change. In contrast to this assumption, this paper presents evidence for a phonetically gradient pattern of aspiration dissimilation found in Aberystwyth English (Wales): an aspiration feature is consistently reduced in the vicinity of another aspiration feature. Two other patterns of gradient aspiration dissimilation have been reported, in Halh Mongolian and in Georgian, which suggests that it may actually be a more general phenomenon. The Aberystwyth data are however better controlled for phonological contexts and lexical regularity than the Mongolian and the Georgian data. The results can then be discussed in light of the two available theories of dissimilation, Ohala’s (1981) hypercorrection theory, and the traditional link with speech errors. Importantly, a number of arguments support Garrett’s (2015) hypothesis that gradient dissimilation might be a(nother) precursor to complete dissimilation. The pattern thus shows how the use of careful phonetic inspection can lead to a reanalysis of our understanding of well-established diachronic processes.