Certificate of Advanced Study

A Certificate of Advanced Study (CAS), also called an Advanced Certificate (Adv Cert, Adv. Cert.), or Certificate of Advanced Graduate Study (CAGS), is a post-Master's academic certificate designed for professional and non traditional students, as well as practitioners who seek a continuing education program to enhance their professional development in fields such as liberal arts, education, library science, software engineering, area studies, data science, public policy, and management.

Source: Wikipedia — Certificate of Advanced Study (CC BY-SA 4.0)