Meaning & use
light-year
A unit of astronomical distance equal to the distance light travels in one year, about 9.46 trillion kilometers.
See it in a sentence
The nearest star system to our sun is a little over four light-years away.
Astronomers measure the size of galaxies in thousands or millions of light-years.
A note on using this word
Despite containing the word 'year', a light-year measures distance, not time.
Words with a similar meaning
This term is best learned through its definition and examples.
Choose a synonym to suit the sentence. Meanings can overlap without being identical.
Make it your own
Write a sentence using “light-year”, then compare your use with the examples above.
Your draft stays on this page and is not sent anywhere.