The Free Dictionary.com

This is an add-on for Internet Explorer. Dictionary is a simple right-click add-on for Internet Explorer that adds the 'Definition' option to the right-click menu. No matter what web site you are visiting, you can now instantly check any word's definition. A very handy and useful extra. One warning though - the results page will try to install a cookie from Avenue A that tracks consumer patterns but otherwise is harmless. If you have spybot installed this will be picked up and you can choose to not receive the cookie but still view the results. Freeware.

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