Also written as "sack-time". Comes from old slang term for mattress: sack.
"I just pulled a 12 hour shift. I need to do some serious sack time."
"If you didn't put in so much sack time, you might get something done."
2. The slapping of a man's ball sack onto another persons face, around their mouth, or in their mouth while the victim is asleep.
2. Bill: WTF is all over my face?!
Jeff: LOLOLOLOL probably a little too much sacktime!
3. Rook got the sweaty backside during his sacktime!