What is a "slowroll"? What is the definition of the term "slowroll"?
A "slowroll" occurs when a player takes a very long period of time to call another player's all-in when there is nobody else left to act AND they know that they have the best hand.
Example #1:
There are two players in the pot and the board reads 8-7-6-K-K. The first player to act pushes all-in. The second player takes his time, re-arranging and counting out his chips for several minutes before finally making the call.
The player who pushed all-in turns over 9-10 for the straight, while the second player (who took an incredible amount of time to make the call) turns over K-K for quads. This is a "slowroll", as there was absolutely no way that the second player was going to fold his hand (as he had the absolute nuts).
Example #2:
You have a massive stack in an online MTT. Action is folded around to the short stack on the button, who pushes all-in. The SB folds, and you look down at pocket Aces.
There is absolutely no way that you are folding this hand (obviously), but you decide to have some fun with the short stack. You use your time bank, letting it tick down to just one second before finally making the call.
This is a "slowroll".
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Not a Slowroll:
There are three players in the pot and the board reads A-A-8-7-3. The first player to act shoves all-in. The second player uses their time bank, letting it tick down to just 1 second before finally making the call. The last player to act in the hand decides to fold after a bit of thought.
The first player turns over K-J for absolutely nothing, while the second player turns over A-A for the stone cold nuts.
This is NOT a "slowroll", as there was still a player left to act in the hand after player 2 (who had A-A).
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Example #3 of a "slowroll":
You are playing in a home game against some of your friends.
With the board reading 8-8-J-Q-K, your friend leads out with a bet and you decide to make the call.
Your friend flips over pocket Sevens. You take your time and pretend like you are going to muck your cards, only to flip over A-J at the last second.
You just "slowrolled" your friend.
Example #4:
Three minutes into this video:
An epic slowroll occurs.. there is no way that Cornils is going to fold his pocket Aces, but he decides to take a "timeout" anyways.
The player who pushed all-in turns over 9-10 for the straight, while the second player (who took an incredible amount of time to make the call) turns over K-K for quads. This is a "slowroll", as there was absolutely no way that the second player was going to fold his hand (as he had the absolute nuts). 
