A stand-in object, placeholder, or imitation used for display, testing, or deception. Common in contexts like crash-test dummies, dummy variables, or dummy products.
Dummy smartphones are displayed at the storefront.
Crash-test dummies are used in collision experiments.
In crash tests, a doll is used as a dummy in place of a human.
They made a dummy of the new product and displayed it at the trade show.
本物 means the genuine, real article, the direct opposite of a ダミー, which is a fake stand-in.
Borrowed from English 'dummy'.