A mental model which blends a new way of thinking with something familiar. The term 'horseless carriage' was a way to introduce the concept of the automobile to a world used to thinking about transportation as horses, qualifying an implied question with a familiar concept: 'How would a carriage function without a horse pulling it?'
"When technologists first introduced the idea of sending messages on the internet, the term 'e-mail' was used as a sort of horseless carriage to make the concept more understandable. Even though far more instantaneous chat messaging was already possible, it was too much of a mental and technological leap for mass adoption."
