The Master Chief is done when the man is multitasking and having doggie style sex with his significant other, while playing halo 3. The man then proceeds to stick the controller handles into the ass and vagina cavities at the same time. Be sure to keep the buttons out so that you can finish the fight.

*Note: Experience may change during online play
I got a killtacular while giving my girl the Master Chief last night!

My girl got doo-doo on my controller when I gave her the Master Chief.
by Adam Kelm June 11, 2008
Attempting to be a one man army.
"Dont you dare go Master Chiefing It." , " That retard just tried to Master Chief It."
by Future Ninja Turtle September 18, 2009
A bad-ass soldier from the video game "Halo: Combat Evolved". Usually seen in green MJOLNIR Mark-V Armor. Synonymous with 1337.
The Master Chief can run at up to 55 kilometers per hour. He is the embodiment of 1337ness.
by Araquiel May 29, 2004
The protagonist from the Halo Series by Bungie. He could totally kick you ass. And you know it.
Master Chief kicked the Flood's ASS in Halo 1, 2, and 3.
by Dayonic November 4, 2007
Master Chief is the name of the rank that John is, his spartan number is 117. He is the playable character in both Halo: Combat Evolved and Halo 2. Hes a badass character, hes so badass that he just has to walk on screen and you can feel the badassness radiating from his badass aura of badassness. He doesn't need to walk on screen and snap some necks or crack some skulls to look like a badass, he just walks on screen. Okay, enough of my undying love for the most badass video game character.
by Vorhees July 19, 2006
If you're playing Xbox Live, and you just so happen to come across someone with the name "Master Chief," you've been blessed.
Now, there are plenty of people that go under that name and then add excrutiatingly long numbers, but if you see the original "Master Chief," consider yourself a child of good luck.
I was playing Halo 2 yesterday and I met the original Master Chief, so I think I'll go gambling today.
by CyberElectric December 10, 2004
When your playing a game where you can just go up to the enemy with your guns blazing and end up taking them all out and not dying.
"Dude the hunters in ODST are really hard! You cant just Master Chief It like in Halo 3"
by Hellz Storm September 18, 2009