Definition of "tun" [tun]

• A large cask for liquids, especially wine. (noun)
• A measure of liquid capacity, especially one equivalent to approximately 252 gallons (954 liters). (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Back on the local (non-EC2) workstation, set up the software: sudo apt-get install - y openvpn sudo modprobe tun sudo iptables - I OUTPUT - o tun+ - j ACCEPT sudo iptables - I INPUT - i tun+ - j ACCEPT"
• "Later the village was surrounded by a wall called a tun, and by a transfer of terms the village frequently came to be called a mark, or tun, later changed to town."
• "-- A tun is a certain measure for liquids, as for wine, and its capacity equals two pipes, or four hogsheads, or 252 gallons."