911

From Rap Dictionary

noun

911

[Nine one one] The US and Canada phone number for emergencies. Now I dialed 911 a long time ago -- Public Enemy (911 Is A Joke [1989]).

9/11

[Nine eleven] September 11th 2001, the day of the terrorist attacks with airplanes on the World Trade Center in New York City and the Pentagon in Washington DC. Like 9/11, you gon' remember this day -- Lil' Kim featuring Missy Elliott ((When Kim Say) Can You Hear Me Now?) [1]

Porsche 911

(Nine Eleven) A popular rear - engined sports car made by German car maker Porsche.