SD is an abbreviation for Sneak Dissers, meaning people who talk behind your back or whatever.
"Ayo there's that fuckin SD"
"Huh?"
"Sneak Disser"
The most beautiful person in the world. He is rich and successful and owns many mansions and many cats, favors his s/o sometimes, and his favorite number is 34.
"fluidswapper is sexy amazing rich successful"
"true"