diagnose

American  

[dahy-uhg-nohs, -nohz, dahy-uhg-nohs, -nohz] / ˈdaɪ əgˌnoʊs, -ˌnoʊz, ˌdaɪ əgˈnoʊs, -ˈnoʊz /

verb (used with object)

diagnoses, present (3rd person singular) diagnosed, past participle, past diagnosing present participle

1. to determine the identity of (a disease, illness, etc.) by a medical examination.

   The doctor diagnosed the illness as influenza.

2. 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.

3. to classify or determine on the basis of scientific examination.

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verb (used without object)

diagnoses, present (3rd person singular) diagnosed, past participle, past diagnosing present participle

1. to make a diagnosis.

diagnose British  

/ ˈdaɪəɡˌnəʊz /

verb

1. to determine or distinguish by diagnosis

2. (tr) to examine (a person or thing), as for a disease

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Other Word Forms

Derived Forms

• underdiagnose
  verb (used with object)
• diagnosable
  adjective
• undiagnosable
  adjective
• undiagnosed
  adjective
• well-diagnosed
  adjective

Inflected Forms

Participles

• diagnosing
  present
• diagnosed
  past

Conjugated Forms

Present

• diagnose
  simple
• diagnoses
  simple
• have diagnosed
  perfect
• has diagnosed
  perfect
• am diagnosing
  progressive
• are diagnosing
  progressive
• is diagnosing
  progressive
• have been diagnosing
  perfect progressive
• has been diagnosing
  perfect progressive

Past

• diagnosed
  simple
• had diagnosed
  perfect
• was diagnosing
  progressive
• were diagnosing
  progressive
• had been diagnosing
  perfect progressive

Future

• will diagnose
  simple
• will have diagnosed
  perfect
• will be diagnosing
  progressive
• will have been diagnosing
  perfect progressive

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.

Example Sentences

See Examples For:

diagnose diagnoses diagnosed diagnosing

I’m not saying to try to diagnose her from afar; in fact, a manager asking an employee about their health can be illegal in certain situations.

From MarketWatch ● Jul. 29, 2026

Such a test could potentially help diagnose Alzheimer's disease, determine its stage, and identify a patient's particular disease subtype.

From Science Daily ● Jul. 22, 2026

The Canadian Medical Association Journal chronicled his family taking him to get emergency care over the following days and both clinics and hospital doctors trying to diagnose his symptoms.

From BBC ● Jul. 2, 2026

Start-up Wunderfix meanwhile offers repair services linking retailers, customers and shops via an application that allows cyclists to diagnose and, where possible, repair their bicycles themselves.

From Barron's ● Jun. 28, 2026

“That’s right! We should diagnose you first. Once we find out what is making you sick, we can heal you.”

From "Healer of the Water Monster" by Brian Young

The figures show the disease is decreasing slightly among older adults – who still make up the largest proportion of new diagnoses.

From BBC ● Jul. 22, 2026

Together, they account for millions of new cancer diagnoses worldwide each year and remain among the leading causes of cancer related deaths.

From Science Daily ● Jul. 14, 2026

While chatbots are the new Dr. Google for a lot of people seeking medical advice, eating-disorder therapists say advice offered to their patients without the context of their diagnoses is downright dangerous.

From The Wall Street Journal ● Jul. 11, 2026

Neuroscientist and autism expert Gina Rippon says an increase in late autism diagnoses around the start of this decade revealed the myriad of coping mechanisms women had been employing.

From BBC ● Jul. 7, 2026

Though still in his studies he was certain of various diagnoses he’d made about the state of the man’s health.

From "The Underground Railroad: A Novel" by Colson Whitehead

Through 2022, the Boston University CTE Center studied the brains of 376 former NFL players and diagnosed 345 with CTE, a rate of 91.7%.

From Los Angeles Times ● Jul. 30, 2026

John Barry was diagnosed with dementia in 2018 and died from the disease in 2024.

From BBC ● Jul. 29, 2026

When Julia was diagnosed in childhood with celiac disease, Mommy continued loading her up on gluten with grievous consequences.

From The Wall Street Journal ● Jul. 28, 2026

My mom’s husband was recently diagnosed with cancer.

From MarketWatch ● Jul. 28, 2026

What had I thought when I first got diagnosed?

From "How to Disappear Completely" by Ali Standish

These particles may offer new biomarkers for diagnosing Alzheimer's disease and determining how far it has progressed.

From Science Daily ● Jul. 22, 2026

The “why” could be bad luck, better awareness in diagnosing concussions or something else.

From Los Angeles Times ● Jun. 14, 2026

New guidelines have been issued for diagnosing and treating the disorder.

From The Wall Street Journal ● Jun. 12, 2026

I know that real problem-solving starts with diagnosing the root cause.

From BBC ● May 29, 2026

He asked Howard Jones to contribute an article recording his memories of diagnosing Henrietta’s tumor.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot

Related Words

• analyze
• determine
• investigate
• pinpoint
• pronounce
• recognize