disabuse

Here's a great word for being condescending to a friend or anyone you think is misinformed, misguided or otherwise just plain wrong. To tell someone that you will enlighten them, or explain where they've been mixed up is one thing, but to use the word "disabuse" is almost to suggest that they are a child who doesn't know any better. It is seldom used by someone who sees their illusioned acquaintance as an equal. It's excessively patronizing. As in, "Give Mommy that misconception before you hurt yourself with it!" I don't know quite how "disabuse" came to mean what it does, given the standard definitions of the root word. Perhaps there is some link to the apparently obsolete "To deceive or trick" definition of "abuse." (Found on dictionary.com)