What is a light year?

Level: Primary / Intermediate

This is a great time to use google's define feature.

The trick is to type the word define: (with the colon) in front of the word you want to define, then click Search, so define:light year. This searches for all the meanings on the web that define your word.

HOT TIP: Reading a few different definitions will help your understanding of the topic. If you don't understand, keep looking for one that uses language at your level.