Finding word definitions on the web just became easier, thanks to a new extension for Google Chrome . With this feature installed, simply double-clicking a word on a web page activates a pop-up with a definition of that word.
To give it a try, head over to the Chrome Web Store  and click the Add to Chrome button (it’s only available for Chrome).
In the Confirm Installation dialog box, click Install.
One of two ways to find a definition is to click the Google Dictionary icon on the toolbar, type a word, and click the Define button.
Although, as mentioned above, the true beauty of this feature is the ability to simply double-click a word on a web page to find the definition (to hear the word spoken, click the speaker icon).
If the definition provided isn’t the one intended in the text, or if you’re just looking for a different, or more comprehensive definition, click the More link (lower right corner of the pop-up) to open a page with expanded choices.
You can also double-click a word within the pop-up to find a definition for that word.
To manage the Chrome dictionary extension, right-click the icon and select Options.
Shown below, in Options, the Ctrl key was added as a trigger. This way, holding the Ctrl key, while double clicking the word, is necessary to pull up a definition, avoiding an automatic pop-up each time a word is double-clicked.
Several complaints are posted on the download page, mostly involving language translation. As someone who speaks one language with only relative fluency, this was not a problem for me, but it’s something to consider if you’re looking for foreign language definitions.