The latest update for the free Dicionary.com app for iOS (iPhone and iPad) includes a number of interesting enhancements.
Dictionary.com 2.0 (iTunes App Store)
Words and their definitions can now be shared via email, Twitter and Facebook. An interesting new twist to the app is the ability to see which words were searched within five miles of your location. These words are placed on a map. This new feature is named “Nearby Words.” Trending word searches in your area are visible in a tag cloud beneath the Nearby Words map.
You can find these new location based features in the “Daily” word section of the app. You can turn off the app’s ability to determine your location by turning it off in the iOS Settings section for Location Services.