Large, beautiful breasts that are keep well consealed and initially appear to be much smaller and less impressive than they actually are until unleashed.
The act of ejaculating all over a friend or roommate's bed when they are out with the key being not telling them when you have committed the act till a much later date.
Can be used as a very credible threat.
"My brother didn't want to let me use his PS3 so I gave him some sneaky sleepers"
As a threat,
"Pay your half of this month's rent or i'll leave you some sneaky sleepers"
1. to conceal an alcoholic beverage, typically of the can variety and of high alcohol content, within the confines of one's hockey-jersey-sleeve while in public.
2. a strategic pre-game move that allows one to continue consumption while utilizing public transit in efforts to avoid ass-rape beer prices at the venue.
James: "Sir, I'm afraid we must leave this here Branch Avenue, for I fear that we will miss the dropping of the puck if we continue to partake in consumption of this delicious DC Brau. A pity it is to leave this beer behind."
Joseph: "Fear not, good sir, for tonight we are sleevenit on the Metro in our Washington Capitals hockey jerseys!"
It's when you have a late night conversation (usually while on the phone), while very sleepy. The next morning, you forget what you were talking about towards the end of the conversation.