510(k)
A submission asking the FDA to agree that a new device is close enough to one already on the market.
Most devices reach the US market this way. The manufacturer names an existing legally marketed device, the Predicate device, and argues the new one is substantially equivalent to it in intended use and technology. What the FDA reviews is that comparison, not the underlying safety evidence. This is why devices on this route are called cleared, never approved. The name comes from the section of the Food, Drug, and Cosmetic Act that requires the notification.