from The American Heritage® Dictionary of the English Language, 4th Edition
- transitive v. To render useless or ineffectual; cripple.
- transitive v. To cause to appear stupid, inconsistent, or ridiculous.
- transitive v. Law To allege or prove insane and so not legally responsible.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. To prove to be of unsound mind or demonstrate someone's incompetence.
- v. To cause to appear foolish.
- v. To deprive of strength or efficacy; make useless or worthless.
from the GNU version of the Collaborative International Dictionary of English
- transitive v. To make foolish; to make a fool of.
- transitive v. To regard as a fool, or as foolish.
- transitive v. To allege or prove to be of unsound mind, so that the performance of some act may be avoided.
from The Century Dictionary and Cyclopedia
- To make or cause to appear foolish; reduce to foolishness or absurdity: used of persons or things.
- To look upon as a fool; regard as foolish.
- In law, to allege one's own insanity.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. deprive of strength or efficiency; make useless or worthless
- v. prove to be of unsound mind or demonstrate someone's incompetence
- v. cause to appear foolish
Late Latin stultificāre, to make foolish : Latin stultus, foolish; see stel- in Indo-European roots + Latin -ficāre, -fy.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Latin stultus "stupid, foolish". (Wiktionary)