We started with a standard word list for validation called ENABLE2k that is often used for word games and word game tournaments. People and Chumbots use the exact same list..except some of the easier Chumbots can't use parts of the list. It's used by quite a few games and you can search google on it if interested. However it only has words and not definitions. We look definitions up via a service called Wordnik.com which does not have definitions for all the words on the Enable2k list. Scrabble's list is copyrighted so we cannot copy it directly. The link for their list is below in case you are curious.
We added the definitions as a bonus feature to provide many definitions for the curious. However there are very few sources we can access easily and legally from the app. Currently our definition source is Wordnik.com but its not connected to the validation list and does not have definitions for every word in the Scrabble lists.
If you find a valid word played that is not valid at either of the dictionary links below we will remove the word and we will give you 3,000 coins for finding it. You just need to verify it is not in either of the Scrabble lists before sending it in. There are some common modern word exclusions we have added (ex. WIKI) that are not yet on the Scrabble list.
This is the link for Scrabble's official list (They have access to an official Merriam-Websters Scrabble dictionary for definitions):
The link above does not always let you search all forms of words and they also need to be checked here:
If you would like to suggest words to add or delete just send us a support request at firstname.lastname@example.org or use Feedback and Support in game and then Send Message.
Thanks for playing and spreading the word!