Mongolian Idiot 

an old term for a retard or someone with mongolism. some, who must be mongolian idiots themselves, like to confuse this term with mongoloid idiot which is not a real term. mongolian idiot is a term within itself. a mongoloid idiot is merely an idiot who is mongolian. DO NOT get them confused unless you want to be a total douche.

that kid is eating his helmet when he should be wearing it. oh he must be a mongolain idiot.

Mongolian Idiot by ursala November 22, 2004

Idiot Mongolism 

The formal term for Down's Syndrome, aka Trisomy 21.

Before the age of Political Correctness when John Langdon Down's was a physician, Down's Syndrome, the genetic condition that he was named after was called Idiot Mongolism.

Idiot Mongolism by Viscount Druitt November 5, 2021