A combined Keyboard Maestro and OSX Automator action to access Princeton’s “WordNet” database. WordNet is a remarkable semantic network of words: not exactly a thesaurus but nonetheless great for hunting down the word you need.
Select a word in any Mac application, hit the keyboard trigger you select and the macros pop-up a window with the corresponding entry in the WordNet database.
Be sure to try clicking on the “S:” link for semantic relations. ‘Hypernyms’ (more general terms), ‘hyponyms’ (more specific terms), ‘pertainyms’ (pertaining to…), ‘meronyms’ (name of the parts of a thing) and ‘sister-terms’ are all good places to start exploring the network.