An evolutionary product or trend that appears to be more or less pathological (as the immense size attained by certain dinosaurs)
This definition was taken from the national Spelling Bee. This information was found at http://calorielab.com/news/2009/06/07/dr-j-about-arrhostia/
I don't know, it sounded good to me when I watched the bee a few weeks ago, but now I'm not sure I understand it, and I can't seem to find a better definition. Help? I quite like this word.