false positive


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 Given that heavy smokers over 50 are at 64 to 111 times greater risk of lung cancer compared to the general population, the risk of false positives is greatly overshadowed by the benefits of early diagnosis. Doru Paul, Verywell Health, 15 Nov. 2023 Cameras connected to hot list databases that haven’t been updated have produced false positive hits, the Texas A&M Transportation Institute reported in a 2021 study. Myah Taylor, Dallas News, 5 June 2023 Say a detection tool has a 1 percent false positive rate—an optimistic assumption. Christopher Beam, WIRED, 14 Sep. 2023 Read on for a breakdown of NIPTs, when NIPT false positives are more likely, and how to make the best decision for you. ​wendy Wisner, Parents, 10 Aug. 2023 In situations where probable cause is required for search warrants or arrests, false positives could lead to unnecessary infringements on individuals' rights. Amber Smith, Discover Magazine, 27 June 2023 If, on the other hand, a test returns positive and the value rises, a false positive is less likely. Mara Buchbinder, STAT, 29 Oct. 2023 But officers were worried the dog’s fatigue yielded a false positive. Nicole Asbury, Washington Post, 25 Oct. 2023 One bugaboo for universities has been false positives. IEEE Spectrum, 1 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'false positive.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1912, in the meaning defined above

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

Dictionary Entries Near false positive

Cite this Entry

“False positive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/false%20positive. Accessed 6 Dec. 2023.

Medical Definition

false positive

: 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
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