once
US /wʌns/
UK /wʌns/
1.
on one occasion or for one time only
:
•
I only met him once.
•
You only live once.
2.
in the past; formerly
:
•
He was once a famous actor.
•
Once upon a time, there was a princess.
1.
as soon as; when
:
•
Once you finish your homework, you can play.
•
Once he arrived, the meeting began.