from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Extreme folly or stupidity.
- n. A foolish or stupid utterance or deed.
- n. Psychology The state or condition of being an idiot; profound mental retardation.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The state or condition of being an idiot; the quality of having an intelligence level far below average; mental retardation.
- n. An act lacking intelligence or sense; an instance of senselessness; extremely foolish behaviour.
from the GNU version of the Collaborative International Dictionary of English
- n. The condition or quality of being an idiot; absence, or marked deficiency, of sense and intelligence.
from The Century Dictionary and Cyclopedia
- n. The state of being an idiot; natural absence or marked defect of understanding; mental imbecility. See idiot.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. extreme mental retardation
From idiot.(American Heritage® Dictionary of the English Language, Fourth Edition)
Could be from Ancient Greek ἰδιωτεία (idioteia), or perhaps simply from idiot + -cy. (Wiktionary)