once upon a time
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once upon a time
A long time ago in the past. Used predominantly as a clichéd opening to fairy tales or stories for young children. Once upon a time, there lived a princess who was training to be a fearsome warrior. Even I was young once upon a time, if you can believe that.
once upon a time
Cliché once in the past. (A formula used to begin a fairy tale.) Once upon a time, there were three bears. Once upon a time, I had a puppy of my own.
once upon a time
On some past occasion, as in I may have sung this piece once upon a time, but I don't really remember it. This phrase, first recorded in 1595, is frequently used as the opening line of fairy tales and stories told to children, as in Once upon a time there was a king who had three beautiful daughters.