Plural of Diagnosis
Table of Contents
TLDR
Singular and Plural Forms
Singular |
Plural |
diagnosis |
diagnoses |
The plural diagnoses is pronounced /ˌdaɪ.əɡˈnoʊ.siːz/ (dye-uh-NO-seeze).
Confusing Plural Forms Exercise
This exercise focuses on confusing plural forms, including Diagnosis.

How to Use "Diagnosis" in Sentences
Singular Example:
✅ The doctor gave her a diagnosis of diabetes.
✅ His diagnosis was confirmed after further tests.
Plural Example:
✅ The hospital handles many diagnoses every day.
✅ Several diagnoses were considered before deciding on treatment.
Common Mistakes
❌ "Diagnosises" (Incorrect) – The correct plural is diagnoses.
❌ "One diagnose" (Incorrect) – The singular is diagnosis, not diagnose (which is a verb).
❌ "A diagnoses" (Incorrect) – Diagnoses is plural, so it cannot take "a".
When to Use "Diagnosis"
-
In Medicine – "His cancer diagnosis was early, which helped with treatment."
-
In Psychology – "The psychologist provided a diagnosis of anxiety disorder."
-
In Problem-Solving – "The mechanic’s diagnosis revealed a faulty engine."
FAQs
What is the plural form of diagnosis?
The plural of diagnosis is diagnoses.
How do you pronounce "diagnoses"?
It is pronounced /ˌdaɪ.əɡˈnoʊ.siːz/ (dye-uh-NO-seeze).
Do we say "this diagnosis is" or "these diagnosis are"?
-
Singular: "This diagnosis is correct."
-
Plural: "These diagnoses are serious."
What is the difference between "diagnosis" and "diagnose"?
-
Diagnosis = noun (e.g., "The doctor made a diagnosis.")
-
Diagnose = verb (e.g., "The doctor will diagnose the patient.")