Use the built-in dictionary feature to define unfamiliar words.

1. While reading, press and hold the word you'd like to look up. An underline will appear beneath the word.
   
2. Lift your finger from the screen. The word's definition will appear.
   
3. Tap the screen to close the dictionary. 

Note: The dictionary may not work in some books such as PDFs, books you borrowed from a public library, or free books you found on the internet.

You can also add new dictionaries to your eReader. Follow the steps in this article to learn how:

• Add new dictionaries to your Kobo eReader