A fork of Rural Dictionary
The act of applying to a prestigious university with a low acceptance rate (such as Harvard or Yale) without additionally applying to a designated "safety school" or having a back-up plan in case the chosen school does not accept the applicant-- similarly to the Hail Mary play in football.
"So what schools are you applying to?" - "Just Princeton, yolo man..." "What about your safety school man, that place has like a 10% acceptance rate!" - "Nah man, I'm pulling a Yale Mary!"