The purpose of this paper is to show that the use of Swadesh lists in language documentation can bring to light the complex and multilayered variation that exists in archipelago settings. The Swadesh list under study reveals that the traditional divide between acrolect and basilect on the one hand and between leeward and windward varieties on the other does not reveal well-defined boundaries across the lects/varieties, except to demonstrate the dramatic variation that occurs within the same oral language. We show that Le Page & Tabouret-Keller’s (1985) proposal that speakers consistently mix lects rather than confining themselves to one point of the creole continuum is supported by the empirical evidence found in the Swadesh list. Coseriu’s (1981) three-dimensional model of diasystematic variation is also validated: the three dimensions involving diatopic (regional), diastratic and diaphasic (spoken, oral language) variation illustrate that the development of any language can be best described by taking into account the fundamental distinction between written and spoken language which cannot be reduced to diasystematic differences. This ultimately points to the importance of the idiolect as a crucial site of variation (Mufwene 2001).