Google Play Books has the awesome feature of storing books on your device so you can read them when you're offline. This is really useful when you're traveling -- especially on a plane -- because you may often lose signal. Unfortunately, when your signal is gone and you want to look up a word, you're out of luck. Until now.
For situations like these, Google has added an offline dictionary that you can download to use at your convenience. Here's how to get the offline dictionary:
Note: The dictionary is currently only available in English.
Step 1: Highlight a word in your book by pressing and holding it. When the definition pops up at the bottom of the screen, slide it up to reveal the full definition and a download link.
Step 2: Tap the download link on the additional information card to store the dictionary on your device..
Step 3: Make sure the download was successful by going to Settings > Offline dictionary and you will see the word "English" under it. If it says None, repeat the steps when your connection is more stable.
Now when you're lacking a signal, you'll still be able to look up the definition of a word.