A catwalk (also known as a runway) is a narrow, usually flat platform that runs into an auditorium or between sections of an outdoor seating area, used by models to demonstrate clothing and accessories during a fashion show.

In fashion jargon, "what's on the catwalk" or similar phrasing can refer to whatever is new and popular in fashion. The term catwalk was established in relation to narrow bridges used for construction. With the narrow platform structure, models walked with extreme caution and poise to avoid any falling or running into other models. Because of their graceful stature and careful walking, many referred to the runway as the catwalk, reminding them of the same grace and poise mimicking a cat's natural walk.

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