Derives from the root word "mongoloid"; A term for the king of all mentally retarded people. Not necessarily used to describe someone with Down's Syndrome, this term is to be saved only for those who are so stupid, they shouldn't even be alive.
This f*cking Mongoloidius Prime in front of me slammed on his brakes at a green light!! Fml.
by Fitz$Gerald August 24, 2010