Dais

Dais is a raised platform  usually in front of a room, for a lectern, throne, seats of honor, etc.

Although I know this word long before I decided to include it here because I usually encounter this word while playing Scrabble. Most often players place ai first then when situation becomes tough, like there's nowhere to place your tiles, adding a d and an s could save you from passing or getting your tiles exchanged which is not a good idea because you'll lose turn and points.  Although it doesn't give you a winning score it certainly gives you a room for two new tiles for your next turn.