A clever nickname to a person with the name of "Vaughn". This just means that you know Vaughn well enough to make a funny nickname making his name sound like the word "vagina"
Vaughn: Hey Ryan, whats up?
Ryan: Vaughngina!!!!! Dude i haven't seen you since we were at Erick's a couple of weeks ago!!
Vaughn: (chuckles at your clever nickname) Yeah bro its been a while.