The top of the food chain in the respective industry, company, group, etc. Usually highly regarded and often unjustly intimidating or feared. The head hauncho runs shit.
Summer of 72 - Somewhere in Europe
Bob Weir: yo do you want to split this ten strip with me?
Phil Lesh: No i’m good, i took a tab in amsterdam and Head Hauncho Jerry told me i freaked him out with that mask i wore
Put your left and right arm horizontal in front of you (left on top of right) and then try to keep them in the same position while hopping up and down multiple times for many hours and many years.