Windows Defender, the name itself states that it only supports Windows platform. Soon Microsoft will be defending Mac OS too with the name of Microsoft Defender Advanced Threat Protection (ATP). Previously, it was known as Windows Defender ATP. According to Microsoft, Mac OS will be the first platform Microsoft is providing its software.
The main reason behind the name update is to expand the coverage of their own product. If you have been using the Windows Defender software before, then you would not face any difficulty in using the Microsoft Defender on your Mac. All the provided feature in Mac is the same as in Windows 10.

With the Microsoft Defender ATP enterprise, it brings all the features to the Mac OS such as network protection, threat isolation, and website reputation. The new Microsoft Defender will be available on Mac devices which are running on Sierra, High Sierra, and Mojave. As part of the trial program, Microsoft allows only the existing ATP customers to try the new Microsoft Defender.

In conclusion, after the Mac, Microsoft could be working to roll out the feature to the Linux platform too. Head over here to try the new tool. For more information about this tool kindly refer to this page.