It is hard to understand posts on modern spirituality. I have heard others speak about how words cannot describe the experience.
Partially I believe this is because language absorbs culture over time. The result of this in English is that it is now difficult to discuss vaguely spiritual terms. For evidence, look at the terms Compassion, Love, Transcendence.
People working on the body of spiritual knowledge must create and adapt language to better fit the content. After all, this is how language evolves.
In the short-term though, it is hard to read work across different schools of spiritual philosophy. A dictionary shared across schools would make understanding and appreciating the content a much less arduous task.
The risk of not having a common language is that knowledge produced will not proliferate like it should. Cross school communication is partly what made the philosophies of Ancient Greece so great, this resulted in a lot of overlap in language used and acknowledgement of concepts amongst the schools.
I hear that Chinese philosophers use an entirely different language from the everyday Chinese so that the delicate and nuanced language required for philosophy is less easily corrupted. Perhaps there is already something like this implicitly forming in English in a non-formal manner.
I don't have the solution to this, and I have not seen anything that solves it. Currently there is no straight forward language that we can use. As often as I can, I will attempt to use the words used by others when discussing spiritual philosophy, but it will be an ongoing task to spread understanding amongst all the people thinking about these things.
If anyone knows about good sources of a shared language for the works in meditation, mindfulness, suffering, compassion, conceit, and the dozens to hundreds of other spiritual concepts we are working on, please share in the comments. For now I'm going to be trying to align myself with the works of Sam Harris and Joseph Goldstein.
Good luck in your search.