Microsoft has been using the "Metro" name to describe the new geometric, typography-heavy look-and-feel that is central to Windows 8—and is spreading across the company's entire range of products—ever since it first showed off Windows Phone.

But sources are telling us that this is coming to an abrupt end after the company's Legal and Corporate Affairs team sent out a memo banning the word "Metro." LCA's memo reportedly says that Microsoft has been threatened with legal action for infringing on "Metro" trademarks held by German retailer Metro AG.

From now on, the new terminology that Microsoft is using is "Windows 8-style UI" when talking about Windows 8 applications, and "New User Interface" when talking about the company's full product line-up.

Asked for comment, a Microsoft spokesman told us: