He'd have to have heard of such a thing to attribute it. Azeroth didn't have the term, though it surely had the affliction, and Wrathion likely would recognize it if he saw his companion in the throes of it.

But the human isn't. Not yet. He can take pride in the fact that he's holding it together so well that Wrathion can't tell.

"I'm not fond of staying in cities, unless I've no other choice. I find them...a bit cramped, even at the best of times. I'm sure you understand."

And, even better, it's true without lying!