The term Bidayuh (Bi= people of, Dayuh= land) encompasses the Bukar-Sadong, Jagoi-Singai, Salako-Lara and Biatah. I had a discussion one day with a friend who believes that the term Bidayuh is a misnomer.
The culture and language is different from each of the groups in varying degrees (the Biatah sitting between the Bukar-Sadong and Jagoi-Singai). But the Bukar-Sadong cannot understand the Jagoi-Singai’s language, and vice versa. The bridge would be the Biatah. For the Salako-Lara, their language belongs to the Malayic branch, under the Austronesian languages, categorized with the Iban and Malay languages.
So how did this term came to be? Political reasons. The Salako Lara joined in the 1970s due to their location and minority (although in Kalimantan they have huge numbers). Even the term Bidayuh is a Bukar-Sadong word. It doesn’t mean anything in Jagoi-Singai (not sure about Biatah). Strength in numbers kan?
**Update (6/1/14): The Jagoi-Singai/Biatah equivalent to the term Bidayuh would be Bi-Doyoh in their own dialect.
The friend mentioned that the word Bidayuh could be applied to the Bukar Sadong, but the others should be called by their own names eg. Dayak Biatah, Dayak Jagoi, Dayak Salako etc. Over in Kalimantan, the term Bidayuh doesn’t exist as an umbrella term, instead the Dayaks (who are most like their Sarawakian Bidayuh counterparts) call themselves based on geography like Dayak Sekeyam, Dayak Sontas etc.
There has been calls by some quarters to create a single lingua franca among the “Bidayuhs” so as to turn it into formal education easier. The choice is usually Biatah as it shares commonality with the other 2 groups (exception being Salako-Lara). Maybe I’m being ethnocentric, but I do find making another group’s language as the titular language a bit hard. Plus the fact that we aren’t all ‘Bidayuh’ in the first place.