Lexicons
This program comes at a time when there is controversy about the copyright-ability of lists of words. Hoot uses the 1998 tournament word list (TWL98) as its initial lexicon (dictionary) and allows you to select others, or create your own. The TWL98 is one of the most acceptably shared word list for Scrabble for North America. Currently, the official word list for NASPA Scrabble™ (OWL3) is not available publicly. It is available in print form and can be installed in Zyzzyva if you are a NASPA member. The Collins list (CSW15) is available in Zyzzyva Collins.
Hoot now (1.7.9 and later) also includes the Word Judge 2 lexicon, the official WGPO word list. The Word Judge lexicons contain words up to 21 characters in length and is also suitable for Super Scrabble® games. In order to show words longer than 15 characters in Hoot select the word length in Settings > Options.
Thanks to Maliha Mendoza Mahmood and the The Word Game Players' Organization (WGPO) for allowing me to include the Word Judge lexicons in Hoot. New lexicons are not automatically added to the Hoot database with an update, but can be downloaded from the Hoot website and imported. Other lexicons you can use include the Enable word list, which is what Words with Friends is based on. Yawl is the word list used be WordSmith, another word game.
You can select the lexicon to use by going to Settings and Select Lexicon. You also have the ability to add custom lexicons as well as import and export lexicons. See Lexicon Creator for more information about creating and importing lexicons. See Settings for information about exporting lexicons. The import/export functionality includes the words as well as front and back hooks.
Also within Hoot are Subject Lists and Text file lists. Subject lists are lists of words selected based on a subject. Although Subject Lists may contain words that are not in the selected lexicon, only words in the current lexicon are shown in search results. Text file lists are taken from a text file, but word validity is distinguished. You can download or create your own Subject Lists and add them to Hoot.