lissencephaly 

Smooth Brained not thinking just talking type of guy with no intellect.

Guy 1: Hey you know that guy Dan?
Guy2: Yea, what about him?
Guy1: He must have lissencephaly or something because everything he says is total BS
Guy1: Agreed, Dan is smooth-brained

lissencephaly by BJBone July 12, 2021

Lissencephaloid 

An insult generally used to call another person stupid. Derives from the medical term for smooth-brainedness (lissencephaly). A harder-hitting form of the term "smooth-brain."

Adam: If pro is the opposite of con, what is the opposite of progress?
David: Dude, you're such a fucking lissencephaloid.

Lissencephaloid by Bigolebenis November 5, 2022

Lissencephalic 

Smooth brain 🧠

Andrew Tate is just a lissencephalic Steven Seagal.

Lissencephalic by anonymous December 29, 2022