Not quite.
Windows Defender was released together with Windows Vista, this was very rudimentary and only handled malware and spyware not unlike Malwarebytes, it did not handle viruses.
Microsoft Security Essentials was released standalone sometime during Windows 7's era, this was fully fledged anti-virus.
Microsoft Security Essentials was renamed Microsoft Defender and bundled with Windows starting from Windows 8, where it has stayed to this day.