Highlight text on any website, then search Wikipedia for it with a single click
You can do this with bookmarklets, such as the one you can download on this page.
Follow the above link, and drag the Wikipedia search bookmarklet provided there to your browser's toolbar. This creates a bookmark called Wikipedia search which is actually the activation button for a useful javascript program. The next time you want to look something up while browsing any given web-page, highlight the term and then click on your Wikipedia search bookmark.
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