false positive

noun

plural false positives
: a person or test result that is incorrectly classified as positive (as for the presence of a health condition) because of imperfect testing methods or procedures
A false positive—a test result indicative of disease that isn't actually present—can trigger a chain reaction of worry, further tests, and even unnecessary treatment.Harvard Health Letter
The quarantine could be lifted early if the lab confirms that the case was a false positive.Kathleen Moore
Perhaps more important, polygraph tests are notoriously unreliable. Scientists are understandably concerned about false positive results …Chemical & Engineering News
often hyphenated when used before another noun
The technology could improve a radiologist's ability to detect breast cancers and it could lower the number of false-positive results …Laurie Tarken
compare false negative

Examples of false positive in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Powering Faster Detection And Response At Scale While AI adoption is growing, most security teams are still manually approaching security—triaging alerts, chasing false positives and piecing together context across tools. Expert Panel®, Forbes.com, 10 July 2025 But what if quick action (in response to false positive test results) leads to very painful and expensive prostate biopsies? Bryant Stamford, The Courier-Journal, 3 July 2025 Traders and investors utilize Bollinger Bands in conjunction with other indicators, such as the Relative Strength Index (RSI) or Moving Average Convergence/Divergence (MACD), to confirm signals and minimize false positives. Michael Khouw, CNBC, 23 June 2025 The main risk of the blood test is the possibility of a false positive or false negative, the FDA noted. Youri Benadjaoud, ABC News, 16 May 2025 See All Example Sentences for false positive

Word History

First Known Use

1912, in the meaning defined above

Time Traveler
The first known use of false positive was in 1912

Browse Nearby Words

Cite this Entry

“False positive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/false%20positive. Accessed 15 Jul. 2025.

Medical Definition

false positive

noun
: a person or test result that is incorrectly classified as positive (as for the presence of a health condition) because of imperfect testing methods or procedures
Another problem with the test … is that it also produces a number of false positives; that is, a number of neonates with elevated trypsin levels the first time they are tested are found not to have elevated levels on the second test.The Journal of the American Medical Association
The urine dipstick test for protein can give false positive results when various pharmacologic agents and gross hematuria are present or when urine pH is high …Biff F. Palmer, Scientific American Medicine
often hyphenated when used before another noun
false-positive results that led healthy women to have unnecessary surgery.Denise Grady, The New York Times
The test can give false-positive readings, however, and it triggers a follow-up colonoscopy in 4% to 10% of cases.Marilyn Chase, The Wall Street Journal
compare false negative
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!