LANE: Rory! Rory! The numbers are all adding up, the planets are aligning, and I am going to my senior prom!
In American English, a prom is a ball or formal dance held by a school or college, especially at the end of the academic year for final year students – that is, the senior class. It is is considered one of the essential milestones in a young person’s life, given great weight and significance in US culture. Prom is short for promenade, and the word has been in use since since the late 19th century.
The Annotated Gilmore Girls 