diagnose

1 of 2

verb

di·​ag·​nose ˈdī-ig-ˌnōs 

-ˌnōz, 

ˌdī-ig-ˈnōs 

-ˈnōz, 

-əg-

diagnosed; diagnosing

transitive verb

1

a

: to recognize (something, such as a disease) by signs and symptoms

The other method of diagnosing gallstones is through an ultrasound examination, which has the advantages of being simple, safe and quick.

—G. Timothy Johnson

Pulmonary embolus was diagnosed in two of the actively treated patients …

—Richard D. Sautter et al.

b

: to recognize a disease or condition in

The physicist and cosmologist was diagnosed with Lou Gehrig's disease when he was a 21-year-old student at Cambridge University.

—Maria Cheng

2

: to analyze the cause or nature of

The mechanic diagnosed the problem with the engine.

intransitive verb

: to identify a disease from its signs and symptoms : to make a diagnosis

diagnosable adjective

or diagnoseable

ˌdī-ig-ˈnō-sə-bəl 

-əg-, 

-zə-

diagnosable

2 of 2

adjective

di·​ag·​nos·​able

variants or diagnoseable

ˈdīə̇gˌnōsəbəl 

-īēg- also -ōzə- or ˌ⸗⸗ˈ⸗⸗⸗

: capable of being diagnosed

Examples of diagnose in a Sentence

Verb

The test is used to help in diagnosing heart disease.

Thousands of new cases have been diagnosed in the past year.

The doctor was unable to diagnose the skin condition.

a new doctor with little experience diagnosing patients

The mechanic was unable to diagnose the problem.

Recent Examples on the Web

Verb

Care coordinators – health professionals who help patients navigate the medical system – are often assigned to people diagnosed with cancer or other serious health issues, but they’re rarely made available to postpartum mothers, Griffen said. — Lauren Mascarenhas, CNN Money, 23 Aug. 2026

Wright died peacefully following complications from Marchiafava- Bignami disease, a rare degenerative neurological condition he was diagnosed with in 2015, and complications from heart failure, the family said. — Marlene Lenthang, NBC news, 22 Aug. 2026

She’d previously been diagnosed with rhabdomyolysis, a condition that can be brought on by overexertion, after collapsing from lower-body cramping and temporary leg paralysis during a 2025 playoff series against the Las Vegas Aces. — Brian Hamilton, New York Times, 21 Aug. 2026

The rocker, who joined the Hysteria group in 1992, revealed in 2013 that he’d been diagnosed with Hodgkin lymphoma. — Raechal Shewfelt, Entertainment Weekly, 21 Aug. 2026

Word History

Etymology

Verb

back-formation from diagnosis

First Known Use

Verb

circa 1841, in the meaning defined at transitive sense 1a

Rhymes for diagnose

• arkose
• engross
• faroese
• fructose
• fucose
• gatos
• glucose
• jocose
• morose
• plateaus
• spinose
• vadose

Kids Definition

diagnose

verb

di·​ag·​nose ˈdī-ig-ˌnōs  -ˌnōz 

ˌdī-ig-ˈnōs, 

-ˈnōz

diagnosed; diagnosing

: to recognize by signs and symptoms : make a diagnosis

diagnose a disease

diagnose a play in football

Medical Definition

diagnose

verb

di·​ag·​nose ˈdī-ig-ˌnōs  -ˌnōz 

ˌdī-ig-ˈ, 

-əg-

diagnosed; diagnosing

transitive verb

1

: to recognize (as a disease) by signs and symptoms

2

: to diagnose a disease or condition in

diagnosed the patient

intransitive verb

: to make a diagnosis

diagnosable adjective

also diagnoseable

ˌdī-ig-ˈnō-sə-bəl, -əg-, -zə-