The word "Bidayuh" is derived from "Bidoyoh" which means the people who stay on land.Sometimes we are called the "Land Dayak" - because the Bidayuh main daily life are mostly concentrated on the land unlike the Iban ethnic who dominated the life along the river bank and they are called the "Sea Dayak".
There were no apparent reason why the word Bidayuh is being used instead of Bidoyoh probably because it is literary easy to pronounce. Many names of the Bidayuh vilages are somewhat spelled differently from its original name maybe because it's easier for the non-Bijagoi to pronounce it. Example few of the villages which its name not quite so Bijagoi way of pronounce it
In a more Bijagoi way of pronounce it - sound like so
3. Lassou or Lassow
An example usage of the word "Doyoh"
Someone in the river command his friends to go up to the land "Sus ma'ad ke doyoh kanih" - loosely translated as "Please go up to the land up there"