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undiagnosed

British  
/ ˌʌndaɪəɡˈnəʊzd /

adjective

  1. (of a medical condition, a problem, etc) not having been identified

"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

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.

As a kid with learning differences, whose undiagnosed dyslexia put him behind in school.

From Los Angeles Times • Mar. 4, 2026

In reality, at 57, I had undiagnosed Alzheimer’s disease.

From The Wall Street Journal • Feb. 3, 2026

Controllable endemic diseases like high blood pressure will be undiagnosed and ignored until paralysis sets in.

From MarketWatch • Jan. 26, 2026

The report also recommended that before a neurological condition is declared "undiagnosed," a patient must be seen by two specialists.

From Barron's • Jan. 23, 2026

Ivan Fitzgerald finally isolated the germ that had caused the Finchley girl's undiagnosed illness.

From Omnilingual by Freas, Kelly