Quote Originally Posted by Bjarkmundur View Post
That's an interesting design choice. I've always heard hit dice being correlated with maximum hit points. For example, the modifiers to hit dice based on size from earlier editions. It makes it sound like you actually roll dice to determine a monsters hit points. This would imply that losing a hit die meant you rolled a hit dice to see how much your HP goes down. Specifying hit dice for monsters seems like less 5e than just generalizing 'monsters regain 1/2 of their maximum hit points during short rests'

I completely agree with you guys, I just felt both sides could be argued for.
As a general rule, the only time you 'lose' a hit die is when you spend it to heal, this does not reduce your maximum hp, it's just a way to keep track of your natural healing ability.