ICU
"icu" is a 3-letter English headword indexed on PlainSpell.
The verdict
“ICU” sits in 20 confusable pairs (corpus #20,958) as a noun. The look-alike neighbours are the real trap.
- #20,958
- frequency rank, English
- 2,140
- “I” headwords
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Initialism of intensive care unit.
Corpus desk
Index EN-icu · ICU · English
ICU · rank #20,958 · 0 variants · 20 confusables
- FREQ-MID #20,958
- LEN-MID 3 letters
- VOW-2 2 vowels
- CONFUS-HIGH 20 pairs
- VAR-0 0 variants
- BOOK-MID 2,140
- PHOTO-FINISH Iain
Nearest frequency peer: Iain (-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 “ICU”
Peers at similar corpus weight, separate from look-alike pairs below
- hypnosis
hypnosis
79,045 corpus weight
- Iain
Iain
79,044 corpus weight
- ICU
ICU
79,043 corpus weight
- immersive
immersive
79,042 corpus weight
- impeccable
impeccable
79,041 corpus weight
- inbound
inbound
79,040 corpus weight
What this shows Bars place “ICU” 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 | ICU |
| Language | English |
| Part of speech | Noun |
| Letters | 3 |
| Frequency rank | #20,958 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Corpus rank beside confusables of “ICU”
Easy to mix with look-alikes
The spelling risk for ICU is neighbouring look-alikes ("in", "is", …), not just typos; it is anoun. Frequency #20,958 among 2,140 “I” headwords. 2 recorded senses keep meaning in play.
No generated misspelling entries exist for ICU in our index, which points to an orthography that plays by predictable English rules. It also participates in 20 confusable-pair relationships, "in", "is", "it", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
No explicit etymology string is stored for this entry, so any spelling logic here comes from how the word's sounds map to letters, not a documented origin story. The correct English form is ICU, spelled I-C-U.
Definition
- 1Initialism of intensive care unit.
- 2Initialism of intersection capacity utilization: a measure of the capacity of a roadway intersection.
Recorded use
Wiktionary exampleThese source excerpts show how ICU appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
A day earlier, state epidemiologist Dr. Paul Byers warned the minimal available ICU capacity meant dozens of patients are waiting in emergency rooms for an ICU bed. […] “We desperately needed the nursing support because our ICUs are so inundated with critically ill Covid patients,” Brown said.
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
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Similar English words by spelling shape
Same letter count and similar misspelling depth for "ICU", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 3 letters (nearest by frequency rank).