An action were one will bob their head back and forth in a ridiculous manner while listening to music, and ignoring the outside world.

Common cause for bird facing is unknown but studies may have a direct link related to music such as nickelback, coldplay, justin bieber, and many more.
Example #1

person1: "that chick is totally bird facing right now"
person2: "like a boss, she is probably going to have a headache"

Example #2

bobbing bird

Example #3

when bird facing one will appear to have similar movement to that of a pigeon.
by JewsLoveMyOven August 17, 2012
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When one has indulged a little too heavy on the marching powder, usually without enough alcohol beforehand.
Bro you need to slow down I can’t look at you right now, your bird face is scaring me
by John Tseno November 15, 2022
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