Etsy Rule

A rule that states that an item (typically clothing) is considered vintage if at least 20 years old. Following the requirement on Etsy: "For an item to be considered vintage on Etsy, it must be at least 20 years old"

"Yooo that jacket's sick, is it vintage?"
"I don't have a clue, it used to belong to my uncle who got it around 20 years ago."
"According to the Etsy Rule, your jacket is vintage"