Better than a thesaurus, the Reverse Dictionary is a tool that allows you to describe a concept then returns a list of words and phrases related to that concept. It’s like a thesaurus except that, “[y]our description can be a few words, a sentence, a question, or even just a single word. Just type it into the box above and hit the ‘Find words’ button.”
You can also use *’s for wildcards if you know part of the word you are looking up.
I’m going to keep this site in mind the next time I’m struggling for that perfect word.