Which to use
“illness” and “illnesses” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #3,563
- “illness” frequency rank
- #11,723
- “illnesses” frequency rank
- 15286
- confusion score
Side-by-Side Comparison
| Feature | illness | illnesses |
|---|---|---|
| Definition | An instance of a disease or poor health. | plural of illness |
Where the spellings diverge
Shared letters are muted; the letters that actually set illness and illnesses apart are highlighted. They share 7 letters in sequence, which is exactly why the eye skips the difference.
Spelling & Dictionary Insight
A purely visual mix-up. illness (/ˈɪl.nəs/) and illnesses (/ˈɪl.nəsɪz/) 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 2 extra letter(s) - “illness” sits inside “illnesses”. Our composite confusion score for this pair is 15286, derived from the frequency rank of both members and their visual similarity.
illness is recorded at frequency rank #3,563, classified as anoun, pronounced /ˈɪl.nəs/. illnesses is at rank #11,723, tagged as anoun, pronounced /ˈɪl.nəsɪz/.
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 15286, this pair ranks #464,941 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of illness vs illnesses
Shared letters: eilns. Private to "illness": -. Private to "illnesses": -.
"illness" · 7 letters · shape VCCCVCC · "illnesses" · 9 letters · shape VCCCVCCVC
Known mistypes of this pair
Frequency comparison
Frequently Asked Questions
Can "illness" and "illnesses" be used interchangeably?
Which is more common, "illness" or "illnesses"?
Remembering illness vs illnesses
The fastest way to pick the right one every time.
- Read both glosses above and match the meaning you intend, only context separates this pair.
- See each word in full, definition, IPA, etymology and its other confusables. Full “illness” entry
- Browse more pairs most likely to be confused. Most confusable