A relationship that takes place solely over instant messenger. Couples in an aimlationship may have seen each other face to face occasionally, but most of the interaction has been via the internets.
I was going hook up my friends by letting them talk over AIM first but I ran the risk of them getting into an aimlationship.
The unnaturally pronounced oscillation of the ass during motion such as walking/running. Can be seen in models strutting down the runway, toned high level athletes, etc. Similar to the way a cheetah's shoulder blades oscillate when stalking.
Damn, that girl's got some assillation going on. Look at that bootygo!
or
Those speedskating suits don't leave much to the imagination! You can even see the assillation!