Depending on the sensor it might not be true even to use the mosaic as the determining factor.
I guess the original meaning behind RAW is that the data is raw sensor data, with no interpretation done (though possibly with some processing done). If the camera sensor is a Bayer matrix and the file you get from it is not representing that matrix then it’s not RAW. If there was such a thing as a purely monochrome sensor (perhaps in medical imaging?) then each sensor site would truly be one pixel and the “pixel level” data would still be RAW. Whereas “pixel level” data from a Bayer sensor has to have been demosaiced.
So I think RAW means, “what the sensor recorded” and “RGB” means 3-colour pixel data. It is technically possible that a file could be both (with layered as opposed to matrix sensors). Which is why I don’t agree with the use of “RGB” to (typically) describe demosaiced data.
So for most modern intents, and certainly in the “photographer” market, “demosaiced” is the most meaningful term for “not RAW”.
But then you get Apple, who have branded their use of the new DNG 1.6 specification as “Apple ProRAW” where, in fact, the data in the file is demosaiced. 
