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counterexample

American  
[koun-ter-ig-zam-puhl, -zahm-] / ˈkaʊn tər ɪgˌzæm pəl, -ˌzɑm- /

noun

  1. an example that refutes an assertion or claim.


counterexample British  
/ ˈkaʊntərɪɡˌzɑːmpəl /

noun

  1. an example or fact that is inconsistent with a hypothesis and may be used in argument against it

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of counterexample

First recorded in 1955–60; counter- + example

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

South Africa’s nuclear dismantlement during its transition from apartheid to democracy in the early 1990s offers a positive counterexample.

From The Wall Street Journal

A casualty of the upheavals of the French Revolution, Roland is a dramatic counterexample to the other figures in Ms. Stalnaker’s original and beautifully written book.

From The Wall Street Journal

Argentina offers a solid counterexample: Voters reward discipline.

From Barron's

Another compelling counterexample to the reorganisation argument is seen in a study of congenitally deaf cats, whose auditory cortex -- the area of the brain that processes sound -- appears to be repurposed to process vision.

From Science Daily

I use Denmark as a counterexample in my book, where in the early 20th century their social-democratic party came to power and governed Denmark for three generations.

From Salon