loud cappin 

means to spill someones secrets aloud; to put someone on blast; to tell everyone in the vicinity what someone is trying to sneak and do

Classroom full of people,

Earl: (whispering) Man I got so high last night!

Tyrone: (talking really loud) Whaaat, You got high last night, man why you didn't call me?

Earl: Man why you gotta be loud cappin me like that?

loud cappin by MsDesyBaby October 2, 2010

Loud Cappin 

Speaking on some ones name like they bout it or talking too loud.

Him: MARCUS AINT GONE PUT A HAND ON ME!
Her: He always loud cappin.

Loud Cappin by Mariheartz March 23, 2019