Macniven
A dirty word for when someone sticks their finger up their butt during sex or when they’re getting off, and it might even be someone else doing it to them
I told my friend he was doing a Macniven during his solo shower and he yelled at me
My girlfriend said I was doing a Macniven and I said she was doing it too
My brother’s dog did a Macniven on the couch and it was the worst thing ever