TheFreeDictionary.com Lookup

This add-on enables you to highlight any word on any web page and get an immediate definition for that word. Once a word is highlighted on a page, you can right-click to look up a definition on www.thefreedictionary.com. A new tab is opened right next to your current tab and gets focused so you can immediately see the word definition. When you close that tab, you are taken back to exactly where you were so you can continue where you left off.

Thefreedictionary.com is a superior dictionary that does not force users to view ads like some other commercial dictionaries. This addon attempts to support this great site over those who attempt to profit at every possible turn.