Jack Number
Basically just you're phone number.. but usually said in a rude way or when you're mad. Meaning like the number ain't jack, who the fuck cares..
"Whatever ma, I didn't give no one your jack number.. I'm off this."
or
"Fuck you nigga. You gonna keep sayin that shit then just delete my jack number."
or
"Fuck you nigga. You gonna keep sayin that shit then just delete my jack number."