Privileged Identity Management refers to how people are given access to privilege. In technical terms, it is how people are provisioned into user accounts to provide them with access to a higher level of network privilege.
Other PIM Resources:
Blog
Privileged Identity Management (PIM) and Identity-Centric Security Controls
Delinea Dictionary
PAM vs. PIM vs. IAM - What do all those acronyms mean?
Analysts Reports
Leaders in The Forrester Wave™: Privileged Identity Management (PIM), Q4 2020