assball

Noun (ass-ball) - a strategic defensive maneuvuer where the person wraps their arms around their legs and curls oneself into a ball shape with their ass in the air therefore making their ass vunerable to attack while all vital organs are concealed and safe from harm.

bully- "yo RYAN you owe me 10 bucks im gonna KILL you!"
ryans friend- "quick ryan curl into an assball!"