1) Spontaneous and aggressive use (or threats to use) UNIX administration power to punish users with lesser privileges.
Most often resulting from an overblown ego and heightened sense of self importance linked to root privileges.
2) A cavalier attitude toward others with lesser user privileges.
A characteristic of most Unix System Administrators.
"I got another email from our unix sysadmin threatening to pull me from the sudoers list. He must be having another root rage day"