the chance, etc. of a lifetime
a wonderful opportunity, etc. that you are not likely to get again
When she was offered the job she knew it was the chance of a lifetime.
the trip/experience/opportunity of a lifetime
the chance, etc. of a lifetime
a wonderful opportunity, etc. that you are not likely to get again
When she was offered the job she knew it was the chance of a lifetime.
the trip/experience/opportunity of a lifetime
once in a lifetime
used to describe something special that is not likely to happen to you again
An opportunity like this comes once in a lifetime.
a once-in-a-lifetime experience
That sort of thing happens only once in a lifetime.