mu
/mjuː/
"mu" is a 2-letter English headword indexed on PlainSpell.
The verdict
“mu” is a moderately-common English word, ranked #11,427 in English word frequency and used as a noun.
- #11,427
- frequency rank, English
- 2
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The 12th letter of the Modern Greek alphabet.
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 | mu |
| Language | English |
| Part of speech | Noun |
| IPA | /mjuː/ |
| Letters | 2 |
| Frequency rank | #11,427 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “mu” sits in English frequency
Spelling & Dictionary Insight
The English entry for mu is 2 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /mjuː/. Corpus data places it at rank #11,427 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. The dominant gloss from Wiktionary reads: "The 12th letter of the Modern Greek alphabet.".
Our edit-distance generator produced no likely misspellings for mu, which points to an orthography that plays by predictable English rules. It also participates in 20 confusable-pair relationships, "my", "MW", "MV", 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 μῦ (mû), derived from Phoenician 𐤌𐤌 (mm /mem/, “water”). Doublet of mem. The correct English form is mu, spelled M-U.
Definition
- 1The 12th letter of the Modern Greek alphabet.
Etymology
From Ancient Greek μῦ (mû), derived from Phoenician 𐤌𐤌 (mm /mem/, “water”). Doublet of mem.
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 “mu”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is M-U - every other letter order is a misspelling in standard orthography.
- Say it as /mjuː/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “my” - see the side-by-side comparison. mu vs my
- 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.