by Bob IS Joe December 21, 2021

A society that includes only people with smooth, silky brains who consider themselves as "smart", Except for the Head and co-head that are just heads instead of brains.
by eman laer ruoy esu t'nod November 8, 2022

It’s giving idiot, stupid, the incels of the world. The opposite of someone who can utilise their brain, no grey matter, nothing.
Shan is so smooth brained
by ShanHater47 January 13, 2024

The term "Smooth Brain" refers to someone unintelligent, or an action that could be classified as unintelligent. Neuroscientists believe that the more folds your brain has, the more surface area neurons have, thus, leading to higher intelligence. However, without these folds, there won't be as large of a surface area for your neurons, which leads to idiocy, or Smooth Brainedness.
"This buttery smooth brained idiot stuck a goddamn fork in the power outlet."
"That was the most smooth brained sentence I've ever stumbled across in my 25 years on this planet."
"That was the most smooth brained sentence I've ever stumbled across in my 25 years on this planet."
by Imagine Being Smooth Brained June 12, 2022

A smooth brained robbie is an individual who is unaware of modern slang. They can try but they still won't grasp the current slang, truly they will never be hip with the teens. If you encounter a "smooth brained Robbie" do not hesitate to laugh at their incompetence, because it is funny.
Jeff: "that was awesome, no cap"
Robbie: "why aren't you wearing a hat? Its cold outside."
Jeff: "oh you poor smooth brained robbie".
Robbie: "why aren't you wearing a hat? Its cold outside."
Jeff: "oh you poor smooth brained robbie".
by Soggyfroggy February 22, 2022

When you reply with something smart to a idiot streamer. Famously used by a British world of tanks player that cannot get good dpg's in overpowered tanks.
by PotatoCrusher May 21, 2023

Smooth brain is an insult that refers to an unintelligent person. Supposedly, the intricacy of one's knowledge is represented by the wrinkles on their brain. If their brain is smooth and lacks wrinkles, their knowledge lacks intricacy, and they are therefore stupid.
by GenericGuy3456 May 25, 2024
