Is there an “official” dictionary for SCRABBLE Players?
Yes, Merriam-Webster’s Official SCRABBLE® Players Dictionary, Fourth Edition (OSPD4). For club and tournament play, it is the Official Tournament and Club Word List, Second Edition (OWL2), also published by Merriam-Webster, Inc., and sold exclusively through www.wordgear.com. It is derived from the Official SCRABBLE® Players Dictionary, Fourth Edition, supplemented with nine-letter words and their inflected forms taken from Merriam-Webster’s Collegiate Dictionary, Eleventh Edition (MW11). This book contains words only, no definitions or part-of-speech labels, and includes all inflected forms spelled out in full.