The act of switching to the Danishlanguage while in the middle of a conversation with English or other foreign language speakers.
Mareen: So I was doing the whole drama thing when suddenly my teacher came in and-
Rose: Oh my god, Dagmar, kan du huske dengang vi tog fusen på vores lærer?
Mareen: Stop Danishing on me I don't understand!
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?"