CSI
"csi" is a 3-letter English headword indexed on PlainSpell.
The verdict
“CSI” sits in 20 confusable pairs (corpus #20,894) as a noun. The look-alike neighbours are the real trap.
- #20,894
- frequency rank, English
- 5,599
- “C” headwords
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of crime scene investigation (a term of forensic science).
Corpus desk
Index EN-csi · CSI · English
CSI · rank #20,894 · 0 variants · 20 confusables
- FREQ-MID #20,894
- LEN-MID 3 letters
- VOW-1 1 vowel
- CONFUS-HIGH 20 pairs
- VAR-0 0 variants
- BOOK-DENSE 5,599
- PHOTO-FINISH crochet
Nearest frequency peer: crochet (-2 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 “CSI”
Peers at similar corpus weight, separate from look-alike pairs below
- cricketer
cricketer
79,111 corpus weight
- Crimean
Crimean
79,110 corpus weight
- crochet
crochet
79,109 corpus weight
- CSI
CSI
79,107 corpus weight
- cypress
cypress
79,105 corpus weight
- dal
dal
79,104 corpus weight
What this shows Bars place “CSI” 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 | CSI |
| Language | English |
| Part of speech | Noun |
| Letters | 3 |
| Frequency rank | #20,894 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Corpus rank beside confusables of “CSI”
Easy to mix with look-alikes
The spelling risk for CSI is neighbouring look-alikes ("CT", "CV", …), not just typos; it is anoun. Frequency #20,894 among 5,599 “C” headwords. 5 recorded senses keep meaning in play.
No misspelling variants are generated for CSI in our index, suggesting the orthography follows predictable English patterns. It also participates in 20 confusable-pair relationships, "CT", "CV", "CU", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.
Wiktionary doesn't record an etymology for this headword, so spelling patterns must be inferred from the word's phoneme-to-grapheme mapping rather than from a documented borrowing chain. The correct English form is CSI, spelled C-S-I.
Definition
- 1Initialism of crime scene investigation (a term of forensic science).
- 2Initialism of crime scene investigator.
- 3Initialism of Customer Satisfaction Index.
- 4Initialism of Companion of the Order of the Star of India.
- 5Initialism of consumer safety inspector.
Recorded use
Wiktionary exampleThese source excerpts show how CSI appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
'Damn cops,' said a CSI, who concentrated on the holes in the bark of a tree, the only holes not made by gun-happy rat killers.
This word in other languages
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
How do you spell "CSI"?
What does "CSI" mean?
What words are commonly confused with "CSI"?
What language does "CSI" come from?
Is PlainSpell free to use?
Similar English words by spelling shape
Same letter count and similar misspelling depth for "CSI", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 3 letters (nearest by frequency rank).