to freak out when high off of marijuana or to just be extremely high and just wigging out.
Yo dude, I'm SO high. I'm totally geekin' out! Totally toasted.
v. To act like a geek
in extreme fashion. Also, to act like a complete fangirl
"I always knew you were tough, but tricking the probe by hiding behind the bones of another Super? Oh, man! I'm still geekin' out about it!"
The act of two or more individuals becoming entranced in a conversation about geeky suject matter.
Those two are totally geekin out over the size of their hard drives.