scrabble player who earns their points by adding an "s" or "d" to the end of a high scoring word belonging to another player.

or a player who blocks off certain high point letters or triple word squares, just to prevent the other players from using them.

In general, any practice by a scrabble player that is allowed by the rules, but just seems like an unfair sheist.
Player one: A M A Z E. Ha- double word score, 32 points.

Player two (adds an 's'): A M A Z E S! Double letter AND double word, 34 points.

Player one: You Scrabble Sheister!
by Shumado December 28, 2011
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