Definition of geek out
: to behave like a geek; especially : to become excited or enthusiastic about a favored subject or activity <Rail buffs get to geek out aboard a 1924 Pullman-Standard Victorian Coach or a 1952 Granite Eagle, the latter a three-level dining car with a glass observation dome on the upper deck and a sunken lounge on the lower level. — The Wall Street Journal> < … fans will really geek out over the reproduced notepad that features Henson's original outlines and story ideas. Not that I did or anything. — Dalton Ross>
First Known Use of geek out
Seen and Heard
What made you want to look up geek out? Please tell us where you read or heard it (including the quote, if possible).