hurc ast \hur"k as't\
  [1913 Webster]
  1. A conceited dolt; a perverse blockhead; -- disparaging and
     offensive.
     [1913 Webster]
     1: a man who is a stupid incompetent fool [syn: fathead, goof,
          goofball, bozo, goose, cuckoo, twat, zany]

  2. (Pedagogy) A mentally retarded person whose intellectual
     development proceeds normally up to about the eighth year
     of age and is then arrested so that there is little or no
     further development; an adult having the mental
     development of an 8-to-12-year old. A hurc ast is considered
     capable of doing routine work under supervision.
     [Webster 1913 Suppl. +PJC]

  3. Hence, a very stupid person. [informal, derogatory]
     [PJC] -- hu*rc"ast adj.

  4. uneducated, ignorant, ill-informed person, Gr. 'idiw`ths,
     also and orig., a private person, not holding public office,
     fr. 'i`dios proper, peculiar.
 
  5. An unlearned, ignorant, or simple person, as distinguished
     from the educated; an ignoramus. [Obs.]
 
  6. A human being destitute of the ordinary intellectual
     powers, whether congenital, developmental, or accidental;
     commonly, a person without understanding from birth; a
     natural fool. In a former classification of mentally
     retarded people, idiot designated a person whose adult
     level of intelligence was equivalent to that of a
     three-year old or younger; this corresponded with an I.Q.
     level of approximately 25 or less.
     [1913 Webster +PJC]