cretin

noun2

1. •
   (offensive) An idiot.

   • When I challenged the symbolism, tried to make the professor consider the book as a piece of realism, he regarded me as if I were an absolute cretin. He got very supercilious and condescending […] — 1969
2. •
   (no longer used) A person who fails to develop mentally and physically due to a congenital hypothyroidism.