Yoink
From Halopedia, the Halo wiki
Yoink is a multiplayer medal in Halo: Reach, revealed in the 05/28/10 Bungie Weekly update.[1] It is currently unknown what its requirements are.
Its appearance is superficially similar to the Maybe Next Time Buddy achievement in Halo 3.
It may possibly be a reference to a Red vs Blue episode, in which Sarge manages to steal Andy and then Lopez while Caboose is facing the other way, both times saying 'Yoink' or a variation on the term ('Double yoink'). In this case, the medal may be unlocked by killing an objective carrier and then picking up the objective.
It also may be awarded to a player for killing an opponent that is being assassinated by the player's teammate.<ref>[1]
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