Here’s a nice little shortcut in OS X Lion. Whenever you wanna define an unknown word on a web page, check out the exact definition of that adjective you’ve used in your resume or simply define any selectable word in third-party programs, just double tap with three fingers on a word. Up pops a handy Dictionary window that looks like this. Thanks, @AppleFortyTwo!
By the way, Dictionary is getting a prominent role system-wide, and not only in OS X Lion. We’ve seen Dictionary pop ups in iOS 5 apps such as iBooks and the official SDK allows developers to embed Dictionary pop ups with ease.
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