I propose to make privileges a synonym of permissions.

The synonym is already officially suggested here. If you meet the requirements, you can vote on the suggestion depending on whether you agree or not:

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Some stats about the two tags:

permissions

• 3487 questions
• 41 followers
• Excerpt:

  Short for "file system permissions" - access control based on user, group, or global access.

• Wiki: none

privileges

• 109 questions
• 2 followers
• Excerpt:

  same as permissions "file system permissions" - access control based on user, group, or global access.

• Wiki:

  

> **rwx**, stand for = [**r**]ead | [**w**]rite | [**x**]execute - privileges, that can be either given/added `+` or taken away `-`

> **There are tree groups**:

> - Owner - `u`
> - Group - `g`
> - Other/Everybody Else - `o`
> - ALL OF THEM - `a`