An administrator of a UNIX or Linux box. Someone you don't want to tamper with.
StupidUser:

bash-2.04% write root
I will hax0r j00r r00t! w00t!
EOF

Admin:

bash-2.04$ write StupidUser
Okay, go ahead.
EOF
bash-2.04$ userdel StupidUser
bash-2.04$ rm -rf /home/StupidUser
by EagleRock June 4, 2003
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v. To hack/penetrate/admin a machine - most commonly a datacenter system. Commonly used as an xDCC or FTP server because of its fast connection.
Three of my r00ted machines just came online.
by CH-ris October 20, 2003
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1. Computer geek term for having power or complete control over a computer system.

2. Also used for having power over other stuff.
1. I'm the sysadmin(system administrator) here, and I've got root!

2. In a game of basketball, if you're winning, you'd say, "I've got root on you and this game. And your mom. Bitch."
by GreenChief March 16, 2005
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