xi
/zaɪ/
"xi" is a 2-letter English headword indexed on PlainSpell.
The verdict
“xi” is a regularly-used English word, ranked #5,928 in English word frequency and used as a noun.
- #5,928
- frequency rank, English
- 2
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The 14th letter of Classical and Modern Greek. The 15th in Ancient and Old Greek.
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 | xi |
| Language | English |
| Part of speech | Noun |
| IPA | /zaɪ/ |
| Letters | 2 |
| Frequency rank | #5,928 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “xi” sits in English frequency
Spelling & Dictionary Insight
The English entry for xi is 2 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /zaɪ/. Corpus data places it at rank #5,928 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.
No generated misspelling entries exist for xi in our index, a sign its spelling follows regular English conventions. It also participates in 20 confusable-pair relationships, "XL", "XP", "XO", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Etymologically, the entry records: From Ancient Greek ξεῖ (xeî), ξῖ (xî). The correct English form is xi, spelled X-I.
Definition
- 1The 14th letter of Classical and Modern Greek. The 15th in Ancient and Old Greek.
- 2Either of a pair of hyperons having spin 1/2, which decay into a lambda particle and a pion.
Etymology
From Ancient Greek ξεῖ (xeî), ξῖ (xî).
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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Using “xi”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is X-I - every other letter order is a misspelling in standard orthography.
- Say it as /zaɪ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “XL” - see the side-by-side comparison. xi vs XL
- Browse more English words and confusable pairs in the same reference. English words
Data Source
Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.