Dialects of Malay
Martin and Poedjosoedarmo (1996, p. 5) note that Kedayan is one of the three dialects of Malay spoken in Brunei, the other two being Brunei Malay and Kampong Ayer (otherwise known as Balandih). According to Nothofer (1991), Kedayan shares 94% lexical cognates with Brunei Malay (which he calls ‘BSB’, after Bandar Seri Begawan, the capital of Brunei) and 95% with Kampong Ayer, while it is a little more distant from Standard Malay with 80% lexical cognates, and it is quite different from Dusun, another Austronesian language spoken in Brunei (Gardiner, Deterding & Yabit, 2019) with just 43% lexical cognates. These figures are shown in Table 1, confirming that Brunei Malay, Kampong Ayer and Kedayan are all closely related and they are all three reasonably similar to Standard Malay, but they are more distantly related to Dusun.
Table 1. Lexical cognates (%) between languages in Brunei (from Nothofer, 1991, p. 158)