This is a female that is Extremely stuck up and walks with her nose so far in the air that her nostrils actually point foward making it look like she has a pig nose. This term can be applied in a proper form, as a nick name for one person, or, generically, to refer to stuckup bitchs.
Proper: Who's this girl walking toward us?
That's fuckin Pig Nose, don't even waste your time.
Generic: Did you see that girl?
Ya, what a Pig Nose.
When you stick your fingers into the recipents ASS, pull them out, grab them over the top of the head by the nose with those fingers, and Fuck them in the ass -While telling them to "Squeeel like a PIG!"
See the movie "Deleverance" for references!