(A word that originated in Philadelphia) A stain on one's shirt or article of clothing (either dirt, juice, or sauce etc.), that is usually affiliated with someone sloppy because it reminds the people who see it of children who get stains on their clothes at a young age.
(Gian spills juice on his shirt)
Saeed: Damn yo Gian got a youngbul stain!
(Gian is embarrased and lowers his head in shame)
A Youngbull is someone who is younger then everyone else in the group most of the time a Youngbull is brought into the group by someone the whole group respects and is loyal to...the leader or most respected member of the group is the one who has a Youngbull by his side most of the time.
“Yo don’t fuck with my Youngbull’’
“What up this my Youngbull he with me”