Longman Dictionary of Contemporary English homepage

light year

Related topics: Astronomy, Measurement
light year [countable]
1TMHA the distance that light travels in one year, about 9,460,000,000,000 kilometres, used for measuring distances between stars:
a star 3,000 light years from earth

light years ahead/better etc than something

informal much more advanced, much better etc than someone or something else:
The Japanese company is light years ahead of its European competitors.

light years ago

informal a very long time ago:
It all seems light years ago now.

Dictionary pictures of the day
Do you know what each of these is called?
What is the word for picture 1? What is the word for picture 2? What is the word for picture 3? What is the word for picture 4?
Click on any of the pictures above to find out what it is called.

Explore our topic dictionary