iOS 5 has tons of new features and additions that can make your life a little bit easier. The Lock screen camera icon can help you snap photos quicker, and Shortcuts can make typing long phrases and URLs a breeze.
There’s also a new feature called Dictionary which, as you might have guessed, enables you to look up the definitions of words on the fly. Dictionary is available system-wide, and can be accessed quickly with a single tap…
In almost any application that allows you to select text, you can access iOS 5′s dictionary. Simply tap-to-select a word like you would to cut or copy. In most apps, you’ll get the Define option, but in other apps like iBooks, the option is labeled Dictionary.
Either way, tapping the option will bring up a definition page that includes all kinds of information. Not only does it give you the meaning(s) of the word, it will also give examples of how to use it in a sentence and its origin if possible.
A downside of the feature is that its library of definitions seems to be rather small. If it doesn’t recognize a word, you won’t get the Define option when selecting text. But as a general quick-reference tool, iOS 5′s built-in dictionary works great.