(Fuck-uh-verse-ary) The anniversary date of the first time you and a certain person fornicated.
N: "Really? It hasn't been that long since we started seeing eachother..."
D: "Yeah, it has, its been about three months... you forgot when we first fucked?"
N: "Shit, I forgot our fuck anniversary... our fuckiversary. Tomorrow, Fuckiversary begins."
D: "Ok, were the ... 21st of each month."
A fuckaverssary is a year when you and bae fucked for the first time and you didn't date so this is the date that marks the start of your relationship.
You: Happy fuckaverssary Fabi!
him: Uhh... i guess there's gonna be some tension for the coming days
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?"