idiot savant
         n 1: person who is mentally retarded in general but who displays
               remarkable aptitude in some limited field (usually
               involving memory)

English Dictionary: idiotic	by the DICT Development Group
From WordNet (r) 3.0 (2006) [wn]:
idiotic adj insanely irresponsible; "an idiotic idea" [syn: crackbrained, idiotic] incongruous;inviting ridicule; "the absurd excuse that the dog ate his homework"; "that's a cockeyed idea"; "ask a nonsensical question and get a nonsensical answer"; "a contribution so small as to be laughable"; "it is ludicrous to call a cottage a mansion"; "a preposterous attempt to turn back the pages of history"; "her conceited assumption of universal interest in her rather dull children was ridiculous" Synonym(s): absurd, cockeyed, derisory, idiotic, laughable, ludicrous, nonsensical, preposterous, ridiculous having a mental age of three to seven years Synonym(s): imbecile, imbecilic, idiotic
From WordNet (r) 3.0 (2006) [wn]:
idiotically adv in an idiotic manner; "what arouses the indignation of the honest satirist is not the fact that people in positions of power or influence behave idiotically"
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotcy \Id"i*ot*cy\, n. [Cf. {Idiocy}.]       Idiocy. [R.]
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotic \Id`i*ot"ic\, Idiotical \Id`i*ot"ic*al\, a. [L.       idioticus ignorant, Gr. [?]: cf. F. idiotique. See {Idiot}.]       1. Common; simple. [Obs.] --Blackwall.          2. Pertaining to, or like, an idiot; characterized by idiocy;             foolish; fatuous; as, an idiotic person, speech, laugh, or             action.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotic \Id`i*ot"ic\, Idiotical \Id`i*ot"ic*al\, a. [L.       idioticus ignorant, Gr. [?]: cf. F. idiotique. See {Idiot}.]       1. Common; simple. [Obs.] --Blackwall.          2. Pertaining to, or like, an idiot; characterized by idiocy;             foolish; fatuous; as, an idiotic person, speech, laugh, or             action.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotically \Id`i*ot"ic*al*ly\, adv.       In a idiotic manner.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idioticon \Id`i*ot"i*con\, n. [NL., fr. Gr. [?] belonging to a       private man, private. See {Idiot}.]       A dictionary of a peculiar dialect, or of the words and       phrases peculiar to one part of a country; a glossary.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotish \Id"i*ot*ish\, a.       Like an idiot; foolish.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotism \Id"i*ot*ism\, n. [F. idiotisme, L. idiotismus the way       of fashion of a private person, the common or vulgar manner       of speaking, Gr. [?], fr. [?] to put into or use common       language, fr. [?]. See {Idiot}.]       1. An idiom; a form, mode of expression, or signification,             peculiar to a language.                         Scholars sometimes give terminations and idiotisms,                      suitable to their native language, unto words newly                      invented.                                          --M. Hale.          2. Lack of knowledge or mental capacity; idiocy; foolishness.                         Worse than mere ignorance or idiotism.                                                                               --Shaftesbury.                         The running that adventure is the greatist idiotism.                                                                               --Hammond.
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Idiotize \Id"i*ot*ize\, v. i.       To become stupid. [R.]
From The Free On-line Dictionary of Computing (15Feb98) [foldoc]:
ITU-T X.680          {Coordinated Universal Time}