undiagnosed

adjective

un·​di·​ag·​nosed ˌən-ˌdī-ig-ˈnōst How to pronounce undiagnosed (audio)
-əg-, 
-zd
: not diagnosed : not identified through diagnosis
an undiagnosed illness
… the symptoms of the syndrome may be subtle and thus may remain undiagnosed.—Dwight R. Robinson
a condition that often goes undiagnosed

Examples of undiagnosed 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.
Even if their leaves have been dying from the bottom up, this is often due to undiagnosed spider mites, which are treated by blasting the leaves with a strong jet of water every couple of days. — Anthony Reardon, Kansas City Star, 2 Aug. 2026 Researchers believe, however, that additional infections have likely gone undiagnosed. — Teresa Mull, FOXNews.com, 1 Aug. 2026 Since spring, some 10% of their research participants have been found to have active syphilis — cases that might otherwise have gone undiagnosed and untreated. — Eric Boodman, STAT, 31 July 2026 However, Lindsay’s attorney, Kevin Reddington, has maintained that his client was suffering from severe postpartum depression and undiagnosed postpartum psychosis. — Caroline Blair, PEOPLE, 27 July 2026 See All Example Sentences for undiagnosed

Word History

First Known Use

1864, in the meaning defined above

Time Traveler
The first known use of undiagnosed was in 1864

Browse Nearby Words

undiagnosable
undiagnosed
undialectical
See all Nearby Words

Cite this Entry

“Undiagnosed.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undiagnosed. Accessed 4 Aug. 2026.

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Medical Definition

undiagnosed

adjective
un·​di·​ag·​nosed -ˈnōst How to pronounce undiagnosed (audio)
: not diagnosed : eluding diagnosis
undiagnosed disease
Last Updated: - Updated example sentences
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