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The Visual Dictionary with a new point of view, brought to you by Merriam-Webster. Explore the 15 major themes to access more than 6,000 images and see words like never before.

Urban Dictionary
For those who are interested in contemporary American slang, Urban Dictionary provides an excellent place to start.

Tip:
I use an online dictionary and keep it on my desk top for easy access.Putting a website on your desktop is easy to do. Go to the website you want, look in the Address box and see that little icon at the beginning of the URL? You need to drag it onto your desktop. To see your desk top, click the Restore Down button (the middle one) in the upper right hand corner on your Title Bar to make the window smaller.

The tip above is from  Computer Tips 4 Writers on the Spelling, Synonyms & Stuff page.