Often used to describe exceptional math talent, especially that having been inspired by the great 70's and 80's disco/dance/pop singer Donna Summer. May describe a noun causing lack of care towards math homework, due to Donna's mad beats.
#1: Did you see they figured out how to prove number 17 on our Real Analysis homework?
#2: Yeah, that proof was so Donnarific!
#1: Too bad I still have no idea what's going on in that class.
#2: Who cares about Real Analysis when you've got Donna!?!
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.