Second Selection Search от Lin Yichang

This extension is useful, for example, if you want a traditional search engine (e.g., Google) for general searches, and an online dictionary or Wikipedia as a second search engine.

Usage:

1. Select the text on a web page that you want to search for.
2. Right-click to open the context menu.
3. Click 2nd Search Engine, or hit the keyboard shortcut 2.

The first time you use the extension, the options page opens automatically, where you can easily set up a second search engine. The options page can also be opened from the browser's add-ons manager.

You can either select from the browser's built-in search engines, or enter a custom search URL.