from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An intellectually disabled person who exhibits extraordinary ability in a highly specialized area, such as mathematics or music.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A person who exhibits an extraordinary ability in one subject (often mathematics) whilst being mentally retarded in all other fields.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. person who is mentally retarded in general but who displays remarkable aptitude in some limited field (usually involving memory)
French : idiot, idiot + savant, learned.(American Heritage® Dictionary of the English Language, Fourth Edition)