What does it mean, " an overnight sensation"?
The whole sentence is: His mother told him what it was like to be an overnight sensation. So what does it mean, " an overnight sensation"?
It appears in an documentary video of Audrey Hepburn, her second son came to the fancy hotel where she stayed for shooting the movie Roman Holiday

Question

Answer

to become famous or successful in a day or very quickly, all of a sudden.

Answer

It means that they were unknown or considered to be unsuccessful and then became incredibly famous or successful in a very small period of time.

For example if an unknown actor starred in a film and won an Oscar, they would have gone from 'unknown actor's to 'oscar winner' very fast, they are an over night sensation

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