diagnosesvsdiagnosisConfusable pair

Which to use

“diagnoses” and “diagnosis” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#21,183
“diagnoses” frequency rank
#5,121
“diagnosis” frequency rank
26304
confusion score

Side-by-Side Comparison

Feature diagnoses diagnosis
Definition plural of diagnosis The process of, or an instance of, identification of the nature and cause of a medical condition or illness.

Where the eye mixes diagnoses and diagnosis

Muted = shared; highlighted = the visual trap. They share 8 letters in sequence. diagnoses and diagnosis follow the identical consonant-vowel pattern (CVVCCVCVC). Same shape at a glance is often the real trap, independent of shared letters.

9 ch
diagnoses
9 ch
diagnosis

Visual trap between diagnoses and diagnosis

A purely visual mix-up. diagnoses (/daɪəɡˈnəʊsiz/) and diagnosis (/daɪəɡˈnəʊsɪs/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by a single letter - e in “diagnoses” becomes i in “diagnosis”. Our composite confusion score for this pair is 26304, derived from the frequency rank of both members and their visual similarity.

diagnoses is recorded at frequency rank #21,183, classified as anoun, pronounced /daɪəɡˈnəʊsiz/. diagnosis is at rank #5,121, tagged as anoun, pronounced /daɪəɡˈnəʊsɪs/.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 26304, this pair ranks #387,692 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of diagnoses vs diagnosis

Shared letters: adginos. Private to "diagnoses": e. Private to "diagnosis": -.

"diagnoses" · 9 letters · shape CVVCCVCVC  ·  "diagnosis" · 9 letters · shape CVVCCVCVC

Known mistypes of this pair

  • diagnoses ← daignoses · ddiagnoses · diaggnoses · diagnnoses · diagnoess · diagnosess · diagnosses · diagnsoes
  • diagnosis ← daignosis · ddiagnosis · diaggnosis · diagnnosis · diagnoiss · diagnosiss · diagnossi · diagnossis

Frequently Asked Questions

Is swapping "diagnoses" for "diagnosis" ever safe?
No. They are said differently (/daɪəɡˈnəʊsiz/ versus /daɪəɡˈnəʊsɪs/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "diagnoses" or "diagnosis"?
"diagnosis" is the more common of the two: it sits at frequency rank #5,121 in our English list, against #21,183 for "diagnoses". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "diagnoses" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "diagnosis" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #387,692 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "diagnoses" and "diagnosis" also get mixed up with nearby pairs, the highest-scored neighbour is "diagnose vs diagnoses". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #387,692 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list