1 definition by aithros

Basically means "I've got your back." Comes from the old pilot system in which directions correspond to hours on the clock, where 12 o'clock is forward and 6 o'clock is behind. Thus anyone behind you is "at your six."
Watch out, dude. There's a creep comin' up behind you but I got your six.
by aithros October 6, 2005