An idiot. Originated when a person was annoying their friend in maths class so said friend wrote a note to said annoyer. The note was meant to say "Shut the hell up" but the friend's writing was so bad that the annoyer took the note as saying "Shut the hollup". Therefore the only two people who knew about this new word was the annoyer and the annoyee. It then bacame tradition for the annoyer to tell friends of the annoyee to tell the annoyee that she/he is a hollup, or vice versa. Fun for all the family.
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"