The word comes from decoy. Dekes can involve moving the puck from forehand to backhand, faking a shot, or using your body to sell a move in one direction while going another. The best dekes look effortless because the player has practiced them until they are automatic.
More in general
Top shelf
The upper part of the net, just under the crossbar. Scoring top shelf is considered a skilled shot because it requires accuracy and the ability to elevate the puck quickly. The phrase top shelf where mama hides the cookies is a classic hockey expression.
Empty netter
Goal scored on empty net
Clapper
Slapshot with full wind-up
Muffin
Weak or soft shot