Someone thinks they know something but are totally wrong. They will argue with you even when proven wrong.
The know-it-not-at-all girl argued that vaccines cause autism.
by Cheri Conners RN February 23, 2019
Get the Know-it-not-at-allmug. Governor So-Know-It-All was a general contractor in NH.
by Coop Dupe December 1, 2022
Get the Governor So-Know-It-Allmug. A know it all is someone who thinks they know everything, and refuses to take anyone else's opinion into consideration because, naturally, they know it all. Also known as a Brian.
I have green eyes but my boyfriend Brian insists that I have hazel eyes. Clearly he is a know it all.
by Arniverna September 9, 2022
Get the Know it allmug. A name given to a person that expresses basic common knowledge about a subject, by a person that doesn't know shit about fuck on said subject.
Me: Hey Edgar, maybe you should just check to see if the outlet is blown before you start taking apart the DJ's mixing board.
Edgar: Oh dang man, that actually worked! Quit being such a know-it-all, you're making me look bad.
Edgar: Oh dang man, that actually worked! Quit being such a know-it-all, you're making me look bad.
by Methkateer December 22, 2023
Get the Know-it-allmug. He knows it all 👀. Made by the Grimm brothers as a Grimm fairytale but could pass as a porno name (someone please make this Im being held hostage)
by Dickhead extreme March 3, 2020
Get the doctor know it allmug.