There are a few different doctrines to which one might follow. There are some “tribal” definitions or interpreted uses of the terminology to pertain specifically to the application and intended use. For instance, burlsource.us defines it as such: “wood that has been impregnated with a chemical stabilizing solution. This stabilized wood can then be worked with normal wood working tools.” Note the broad use of “chemical stabilizing solution” in the definition. They do not limit this to acrylates.
Why would we want to stabilize wood? Simple, if you’ve ever seen a beautiful piece of wood rendered unusable due to cracking and checking, you know why. We want to prevent the movement within the wood from damaging our often expensive pieces. Wood will swell and shrink along 3 axis at different rates. The longitudinal direction has almost no appreciable change in most species. The radial and tangential directions however can move 30-100 times more than the longitudinal direction and they do not do so equally. The difference in shrinkage between tangential and radial directions can split a piece of wood apart or warp it drastically as the water escapes the cells within the wood and the wood begins to dry. To prevent this, we must look at several methods by which we can make our wood more “stable” or “stabilize” our wood.