Evasive maneuver

[Julian]

Action taken by a person who spys another person approaching whom he would like to avoid.
[Evasive] maneuvers include:

Ducking down an aisle or into a cubicle to avoid the person.

Turning around mid-stride and walking away from the person before he spys you.

Making up an elaborate (yet plausible) excuse to get away from the person, i. e. I really want to chat, but [I am late] picking up my kids from daycare. It was good seeing you!

Pretending to be engaged in some important act (i.e. a [telephone call]) so the person is forced to leave your presence.