The rear end of something. Can be synonomus with Anus.

1: To be very close behind another aircraft. Either intentionally as in Air Combat, or unintentionally such as on final approach to land. In the second case this will usually result in a late landing clearance, a reqirement to slow down, and even a possible requirement to go around.

2: Expression of expectation for an object, such as a missile, to catch up to, and hit an aircraft.

3: To be very close behind any other object when driving or piloting a vehicle, possibly even expressing a front-to-back collision or stopping incident.

4: a psuedonym for an object being stuck into an anal cavity.
1a: "After combat manuvers I found myself up his six, after which I shot him down"

1b: ATC put us on finals way too close to that Dash-8, we ended up his six and we had to go arond

2: We came up on that Iraqi Mig and I fired a missile up his six.

3: That idiot in the crappy japanise car slammed his breaks on and we ended up his six. There goes my insurance premium, and no claim bonus. Damn it.

4: He's gay. as in he takes it up his six.
by Trent S Hopkinson January 28, 2007
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