WordWeb is an English thesaurus/dictionary add-on for Crossword Compiler. Once you have it installed you can use it from the Clue Editor to look up selected words, or from the Words menu. To look up a word (or a letter pattern) in the grid just press Ctrl+W. It can also be used to automatically format answer words correctly (if this option is selected under Preferences).
For more information on using WordWeb select Help from the WordWeb window's menu.
Information about WordWeb is available on the Internet at https://www.crossword-compiler.com/wordweb.html.