How to define word and download dictionary
The iPhone has built-in dictionaries, where you can look up your new words in email message or on webpage on the fly. iOS 7 or later allows you to download multiple dictionaries.
Select word to be looked up
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Tap to select a word that you would like to define, and hold it down. Then, you should see th "Define" option appear, and tap it.
Tap "Manage"
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Tap "Manage" at the bottom left of the screen.
Download dictionary
Tap the "cloud icon" to download a dictionary you need. When the download is complete, go back to the screen that is showing the word you want to look up.
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Call up dictionary
As you did earlier, select the word and tap on "Define" to call up the dictionary.
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