...that sound, when you yawn so hard that the force is greater than the maximum possible air intake, and you kinda just vapor lock and it rattles your whole head and closes your throat.
Kinda like a cross between a snort and a yawn.
I just realized there's not a name for that as I know of , and we need to coin one here for posterity.
Discuss...and I'll check the coolest funniest answer in the morning and get them a pressie.