Graphical online dictionary

Visuwords is a great online tool for educators, writers, students etc.

You put the word you want to use in an area at the top of the page and press the "go" arrow or "enter".

"A network of nodes or 'synsets' will spring out from the word that you entered. A synset is essentially a single concept that is represented by a number of terms or synonyms. Synonyms are words with different spellings that convey the same idea. For example when you lookup "seem", you see that the word is connected to four synsets each represented by a green circle. Green denotes verbs so all of these synsets represent verbs. Two of these synsets have the lone word "seem"; one has two terms: "appear" and "seem"; and the third has three terms: "look", "appear" and "seem". Each of the four synsets has its own definition. Hovering over a node with the mouse will reveal all of the synonyms for a given synset as well as its definition. Some synsets will also show a few examples of usage. These synsets link to each other and to other synsets according to entries in the WordNet database.
You can zoom the model in and out by rolling the wheel on your mouse. You can click the gray background within the applet and drag the mouse in order to shift the whole model around so you can explore. You can grab any node and pull it away from the others to clarify connections."

By hovering over any word a dictionary meaning will be displayed.

Wonderful tool for the classroom.