Yet as matter of spiritual experience through the use of drugs came up, the nature of this spiritual experience, if supernatural, should be explained?
A pharmacologist or sociologist or whomever has no means to investigate whether or not a given experience is "really" spiritual or supernatural or what have you. But the religious ecstatic state is a concrete phenomenon that can be directly observed. So that, not personal philosophy, is the diagnostic criterion for calling something an entheogen. You don't want a situation where, say, atheist social workers and Christian social workers are handing out different diagnoses to the same clients, based on their personal beliefs rather than an objective criterion. We use consistent terminology because it
works best to use consistent terminology.
Not, as Steve has alleged, to be "politically correct". Frankly, in an age where men like Trump and Putin are calling the global shots, the very idea that practicing the social sciences or medical sciences according to scientific standards rather than emotionally charged language is exactly the opposite of "politically correct", as Steve himself is kind of demonstrating. In our current political regime, someone who agreed with Steve (that barely considered folk categorizations are all you need and medical science is politically correct bunk pushed by the radical left) would be more likely to do well in Washington or the governor's office than someone who is educated on, say, ethnopharmacology. Indeed, if an ethnopharmacalogist had an audience with a senator, they would almost certainly feel obliged by practical need to dumb down their language to the point of being barely comprehensible as their original argument, or they won't get a hearing at all. In short, if you're talking to Gavin Newsom, you're going to have to say "drug", not "entheogen", or he's going to get confused. So what is politically correct?
As it stands, we only have words and terms without references.
Incorrect. A word like "entheogen" or "psychoactive" connects to observeable phenomena and thus ALWAYS has a meaningful referent. What you describe is the situation of vague idea like "a drug", which may or may not have a real world referent, or which might be applied to very different referents by different individuals. Consider the responses you would get if you asked a room of five hundred people "Did you take drugs this week?" Almost all of them will have consumed a drug (like a "drink" or "medicine" or "allergy pill" etc) of some kind that week, but almost none of them woud respond affirmatively, because social conventions have drawn a taboo around the topic, and they have correspondingly become accustomed to a justification like "beer or Sudafed aren't 'real drugs'" to preserve their ability to save face, to the point they have forgotten those even are justifications and not just naturally existing categories.