What meaning can we give to the word “spiritual”?

I am interested in the word “spiritual.”

A thought experiment: Set on one side all formalized religions; set on the other side the entire subculture of New Age literature and practice (most of it westernized travesties of oriental traditions). In place of these, situate an enquiry in the midst of the Greek-born philosophical canon: the triple forces of rationalism, empiricism and pragmatism.

Is there any meaning left to the word “spiritual”?

Is this thought experiment even possible? Is there any way to loosen “spiritual” from the massive baggage that loads it?  If so, where might the enquiry begin?

I find two terms worth exploring: context and essence. Both are philosophically problematic (especially the second). But here is where I would start, deploying a couple of questions as thinking tools, and pushing both of them as far as they can go.

Question 1: What is the context? The prefix “meta” comes to mind. I somehow picture “metaphysics” wrapped around “physics” as the space within which physics sits. To continue this picturing, what would wrap around “metaphysics”? What is the context of the context?

Question 2: What is the essence?  Now the spatial metaphor switches to the deepest interior (from telescope to microscope). For example, what is intrinsic to matter? Is it energy (as contemporary physics seems to suggest)? So then, what is intrinsic to energy? What is the essence of the essence?

By taking these questions to their extremes, might we arrive at a place where the term “spiritual” becomes operational?

I don’t know if this enquiry can bear any intellectual fruit. But as a habit of mind, I find it useful to alert myself to both ends of the spectrum: extreme interiority (the essence of the essence), and extreme exteriority (the context of the context). Is it viable to describe this habit as a spiritual practice?