slackrilege
What Principal Strickland considered behavior dat showed a lack of backbone, diligence, dedication, respect, etc.
While it certainly was true dat most of the indolent actions dat Marty McFly's heavy-handed high-school principal objected to were indeed significantly unwise, said loudmouthed brow-beater was himself a closet alcoholic, and so he possessed plenty of slackrilege in his own behavior. What a hypocrite!