Does the word "spiritual" really mean anything?

The word “spiritual” is thrown around these days as if it’s about something that is uncontroversially known to exists. But I’m quite certain that implication is mistaken. I for one am not convinced.

The dictionary would define it as “of or pertaining to the spirit or the soul.” But that raises the questions, what is the spirit, what is the soul? Does either even exist? Has either been shown by any objective means to exist? Or is it up there with ghosts, demons, gods, chakras, Santa Claus and the Tooth Fairy?
The other definitions equally hinge upon unverified phenomena.

I believe the existence of spirits and souls should be confirmed before we continue considering “spirituality” a serious domain of human development.