CFS
"cfs" is a 3-letter English headword indexed on PlainSpell.
The verdict
“CFS” sits in 20 confusable pairs (corpus #26,716) as a noun. The look-alike neighbours are the real trap.
- #26,716
- frequency rank, English
- 5,599
- “C” headwords
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of chronic fatigue syndrome.
Corpus desk
Index EN-cfs · CFS · English
CFS · rank #26,716 · 0 variants · 20 confusables
- FREQ-MID #26,716
- LEN-MID 3 letters
- VOW-0 0 vowels
- CONFUS-HIGH 20 pairs
- VAR-0 0 variants
- BOOK-DENSE 5,599
- PHOTO-FINISH celebratory
Nearest frequency peer: celebratory (-1 rank slots)
Read with this headword: Spelling guide for this pattern
Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.
Frequency neighbours of confusable “CFS”
Peers at similar corpus weight, separate from look-alike pairs below
- cauldron
cauldron
73,287 corpus weight
- celebratory
celebratory
73,286 corpus weight
- CFS
CFS
73,285 corpus weight
- chalet
chalet
73,284 corpus weight
- Chao
Chao
73,283 corpus weight
- childless
childless
73,282 corpus weight
What this shows Bars place “CFS” against nearest ranked English headwords, not a reprint of the confusable-pair desk.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | CFS |
| Language | English |
| Part of speech | Noun |
| Letters | 3 |
| Frequency rank | #26,716 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Corpus rank beside confusables of “CFS”
Easy to mix with look-alikes
The spelling risk for CFS is neighbouring look-alikes ("co", "CM", …), not just typos; it is anoun. Frequency #26,716 among 5,599 “C” headwords. 3 recorded senses keep meaning in play.
No generated misspelling entries exist for CFS in our index, and the word's spelling is regular enough that our generator found nothing worth flagging. It also participates in 20 confusable-pair relationships, "co", "CM", "CT", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Wiktionary doesn't record an etymology for this headword, so its spelling pattern is best understood through pronunciation rather than a traceable origin. The correct English form is CFS, spelled C-F-S.
Definition
- 1Initialism of chronic fatigue syndrome.
- 2Initialism of cramp fasciculation syndrome.
- 3Initialism of Canada Flight Supplement (a pilot's guide to aerodromes, air control zones, and airways in Canadian airspace and Canadian air traffic control zones).
Recorded use
Wiktionary exampleThese source excerpts show how CFS appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
Over the years, openSNP became one of the largest repositories of its kind, used in research, education, and even community-led investigations like debunking flawed CFS genetic studies.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
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Similar English words by spelling shape
Same letter count and similar misspelling depth for "CFS", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 3 letters (nearest by frequency rank).