Right-click Search Wikipedia
I like this extension because it does just one thing -- as it happens, one thing I need to do all the time -- and it does that one thing with no fuss. Here’s how Right-click Search Wikipedia works: Highlight whatever you want to look up in Wikipedia, right-click, and choose Search Wikipedia. That’s it. The corresponding Wikipedia page shows up in a new tab, and your old tab stays right where it is. If you right-click on a link, Right-click Search will offer to look up the precise text in the link. There’s no icon, just a right-click context menu entry, and the extension doesn’t mess with the original page.