[Publib] "what is the word for..?" stumper

[Tom Cipullo]

here is the question: "What is a word that describes a thing, a state of being as a thing?"
 
this was over the phone; the best I could get is that there is a term (not a literary term) for when you use a state of being to describe a thing.  (he used the word "thing" a few times.)  He did not have an example, or he did, but he took it back: "human," when he realized that wasn't what he meant.  
 
he didn't like "eponymous" (which is the name a person to describe a thing).  maybe it's a grammatical term?
 
so "what do you call it when a term for a state of being is used to describe a thing?" 
 
 
(sorry. if I knew of another place to post this I would. I'm just curious to know if someone knows this.)
 
 
tom cipullo
Palm Beach County Library System, Main Library