To cause to forget or unlearn something. (verb-transitive)
To teach the opposite or contrary of (something previously taught). (verb-transitive)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "unteach" in a sentence
"Alas, many of my students have picked up both assumptions and it's very difficult to "unteach" these tiresome habits of argumentation."
"We've taught them to drink chocolate milk, so we can unteach them that, Cooper said."
"R.A. Dickey wants to unteach himself the knuckleball."