The new iPadOS name was spotted by developer Steve Moser just ahead of when WWDC kicks off in what appears to be the Developer License terms and conditions.
A string of text reads "Apple Software" means Apple SDKs, iOS, watchOS, tvOS, iPadOS, and/or macOS," with iPadOS being a new term referring to the software running on the iPad.
Rumors have suggested the iPad is getting some major updates in iOS 13, which could provide a more PC-like usage experience. There will be new multitasking interfaces with stackable cards and multiple window support, along with a possible tab view.
New gestures are also coming, and with macOS 10.15, Apple is adding tools that will let developers easily port their iPad apps to the Mac.
Moser has also found indications of new PassKit pass types for cars and hotels, which means in iOS 13, you may be able to store temporary cards for unlocking hotel rooms and rental vehicles.