Right now, we have pulled the word lists from a variety of academic and public sources, and integrated in a dictionary to give the mouse-over word definitions.
However, your idea about keywords is something we are *very* interested in doing. Google actually has a search parameter "~" that finds terms like the one you are searching for, and searches for those too.
Another thing we are working on, in the "web stats" tool on Brandfetch is using this Google "similar word" functionality to give you a list of related words to your brand ideas ... so you can see what some associations may be.
Enjoy the site!
That sounds interesting. Do your word lists come from keyword searches online for available domains or from an automated dictionary-like list?