diagnose
Americanverb (used with object)
-
diagnoses,
present (3rd person singular)
-
diagnosed,
past participle, past
-
diagnosing
present participle
-
to determine the identity of (a disease, illness, etc.) by a medical examination.
The doctor diagnosed the illness as influenza.
-
to ascertain the cause or nature of (a disorder, malfunction, problem, etc.) from the symptoms.
The mechanic diagnosed the trouble that caused the engine knock.
-
to classify or determine on the basis of scientific examination.
verb (used without object)
-
diagnoses,
present (3rd person singular)
-
diagnosed,
past participle, past
-
diagnosing
present participle
verb
-
to determine or distinguish by diagnosis
-
(tr) to examine (a person or thing), as for a disease
Other Word Forms
Derived Forms
-
underdiagnoseverb (used with object)
-
diagnosableadjective
-
undiagnosableadjective
-
undiagnosedadjective
-
well-diagnosedadjective
Inflected Forms
Participles
Conjugated Forms
Present
-
diagnosesimple
-
diagnosessimple
-
have diagnosedperfect
-
has diagnosedperfect
-
am diagnosingprogressive
-
are diagnosingprogressive
-
is diagnosingprogressive
-
have been diagnosingperfect progressive
-
has been diagnosingperfect progressive
Past
-
diagnosedsimple
-
had diagnosedperfect
-
was diagnosingprogressive
-
were diagnosingprogressive
-
had been diagnosingperfect progressive
Future
Etymology
Origin of diagnose
First recorded in 1860–65; back formation from diagnosis
Explanation
If you diagnose a disease, you recognize it by the signs and symptoms your patient shows. Your high temperature and the green crud you keep coughing up will allow your doctor to diagnose your bronchitis. The verb diagnose was first used in medicine, meaning "make a diagnosis," or identify a disease by observation of symptoms. Use it to describe the process of figuring it out. If you have bad gut pain, ask your doctor to diagnose your condition. You can also use diagnose for other problems, like if you diagnose poverty and malnutrition as the real causes of a student's terrible behavior, or diagnose the virus that caused your computer to crash.
Vocabulary lists containing diagnose
100 Great Words from "Fahrenheit 451" -- Part I Vocabulary
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Mother's Day Words: What Mothers Do
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
“About Edward Jenner” from the Jenner Institute
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
See Examples For:
What started as an unexpected finding in genetically modified mice helped reveal the cause of an extremely rare disease, transformed how doctors diagnose it, and provided the foundation for developing a drug.
From Science Daily ● Oct. 13, 2026
Just remember: The companies say these are “wellness” devices, not medical instruments designed to diagnose or manage hypertension.
From The Wall Street Journal ● Oct. 11, 2026
After Paul's death, Kate wrote to the health board to complain about how long it took to diagnose him with scabies.
From BBC ● Sep. 30, 2026
And it left me with a question: Why is our mental-health system so quick to diagnose and so slow to examine the full context of a person’s suffering?
From MarketWatch ● Sep. 30, 2026
Unable to diagnose himself, in severe pain, and unable to continue with his work, he presented himself to Dr. Antonia Bagshawe, a physician at Nairobi Hospital.
From "The Hot Zone" by Richard Preston
According to the White House, the aim is to support policy reforms to ensure that women’s research is well-funded and that women have access to “stage-specific prevention, diagnoses, treatment, and care.”
From Salon ● Oct. 21, 2026
The study wasn’t focused on healthcare specifically, but it raises important questions about whether patients and doctors using different languages can reliably receive consistent information about diagnoses, treatment options, and medical risks.
From Slate ● Oct. 16, 2026
There are two main types of lung cancer: "small cell" cancers, which spread aggressively and make up about 10 to 15% of diagnoses, and "non-small cell" cancers, which make up the vast majority.
From Barron's ● Oct. 14, 2026
It looked at people of all ages, but particularly focused on young people and children who have the highest rates of diagnoses.
From BBC ● Oct. 8, 2026
According to the best medical theories of his day, Dr. Harlow diagnoses an imbalance of bodily "humors."
From "Phineas Gage" by John Fleischman
On the night before a game against the Jacksonville Jaguars, Philadelphia Eagles quarterback Jalen Hurts was in London and diagnosed with a blood clot in his leg.
From The Wall Street Journal ● Oct. 21, 2026
Initially, it was diagnosed as a superficial vein clot, and now it is a series of deep vein clots that have since traveled to Hurts’ lungs.
From Salon ● Oct. 21, 2026
She recalled how much he loved the beach, and was devastated when he was diagnosed with skin cancer, which transitioned into brain cancer.
From Los Angeles Times ● Oct. 21, 2026
After suffering two stress fractures in the space of four months, Smith sought professional help and was diagnosed with REDs – relative energy deficiency in sport.
From BBC ● Oct. 20, 2026
“I suppose nowadays, she’d have been diagnosed with something,” Gloria says, shaking her head.
From "How to Disappear Completely" by Ali Standish
"I have been diagnosing PCD for 20 years by examining their cilia waveform, length, cell size and shape," he said.
From BBC ● Oct. 9, 2026
The deal marks a continued push by medical-equipment maker GE HealthCare into the growing market for radiopharmaceuticals, which have uses for both diagnosing and treating diseases including cancer, heart disease and Alzheimer’s.
From The Wall Street Journal ● Oct. 5, 2026
Healthcare professionals “are often undertrained and ill-equipped in diagnosing elder abuse.”
From MarketWatch ● Sep. 24, 2026
Modern therapies can help many patients achieve remission, but diagnosing and managing IBD remains challenging.
From Science Daily ● Sep. 20, 2026
He had been diagnosing and treating the illness since he’d first set foot in Haiti.
From "Mountains Beyond Mountains" by Tracy Kidder and Michael French
Random Word
Spin the wheel and learn a new word!
Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
