Graphwords (http://graphwords.com/) is another thesaurus visualisation tool that uses Wordnet (http://wordnet.princeton.edu/). Type in a word and it generates a map of associated nouns, adjectives, verbs and adverbs.
To view the meaning of a group of words move your cursor over the node and to explore a word and its related terms in more detail simply click on it.
Many thanks to Carol Bream for the alert.
Visuwords (http://www.visuwords.com/) is an online graphical dictionary based on Princeton University’s WordNet (http://wordnet.princeton.edu/). Type in a word and it displays definitions, related terms, synonyms and antonyms as a diagram.
The colours show whether the words are nouns, verbs, adjectives or adverbs and the format of the lines joining them represent the type of link between words. A broken blue line, for example, represents “also see”. Move the cursor over a word to see a definition and double click on a node to expand it. This is a great tool if you are stuck for an alternative word and prefer a visual rather than textual approach to this type of search. It was suggested by one of my European contacts who was looking for a tool to help a colleague draft documents in English.