Defining experiential things in words is impossible. For example, define what the color blue looks like. Not just "it is the color of the sky," or " its a certain wave length of electromagnetic energy, but try to define in words what it looks like in the abstract. The best you can do to convey a definition of an experience is by someone experiencing the thing and then giving it name. Metaphors can also convey some meaning of experiential things--blue is calm, serene, ethereal, peaceful, cold--but then again those are only useful if the other person has experienced it.
most of the irrational argument on this site is from narcissists (they are easy to spot), claiming that an something someone experienced was turquoise, and not the cerulean blue that only they have the ability to see.
