Wordweb is a feature rich software that does much more than a paper dictionary or thesaurus. WordWeb is truly a Word Web - each set of synonyms is linked to other related sets. Look up "tree", click on the "Types" tab and you'll have a list of different types of tree. Click on "Part of" and WordWeb will tell you that a tree can be part of a "forest" or "wood".
The licence is the brilliant thing, myself I have a fear of flying or should I say
crashing so the licence is perfect for me.
Licence: http://wordweb.info/free/licence5.html
Download: http://wordweb.info/ (free or pro)