from Wiktionary, Creative Commons Attribution/Share-Alike License.
Sorry, no etymologies found.
When at the ballgame, when the roof is closed and the action is a bit slow you might be able to use the spectator's head in front of you as a temporary unipod,…be polite… ask first! along with the offering I'll buy ya a beer!
Another master of the inquisition invented a unipod -- a stool with one leg -- sometimes placed in the middle of the seat, sometimes on the edge, on which the unfortunate scholar tiresomely balanced.