The Application Control feature in Windows 10 was originally called Device Guard Code Integrity. This was brought under the Defender umbrella of security technologies as Windows Defender Application Control (WDAC). Microsoft earlier this year announced that Windows Defender would become cross-platform (with a version of Defender antivirus for macOS) and be renamed Microsoft Defender.
In my blog posts I have called it Microsoft Defender Application Control (MDAC). You can see in the screenshot below that all the Defender technologies for Windows 10 Endpoint Protection, in Intune, are now Microsoft Defender.