The response to a listener, who on hearing a story feels that they must interject with a similar comment, or an inference that they are also subjected to a similar environmental variable. Usually this will be more intense the original commentator. The meaning originates from the Punch and Judy shows which have their root in 16th-century Italian commedia dell'arte. The reference being that without the responder, the show cannot go on.

When you eat dirt for the first time and leave your family to build a shack in the woods