rho
/ɹəʊ/
"rho" is a 3-letter English headword indexed on PlainSpell.
The verdict
“rho” is a moderately-common English word, ranked #36,739 in English word frequency and used as a noun.
- #36,739
- frequency rank, English
- 3
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The seventeenth letter of the Modern Greek and Classical alphabets and the nineteenth letter of Old and Ancient.
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 | rho |
| Language | English |
| Part of speech | Noun |
| IPA | /ɹəʊ/ |
| Letters | 3 |
| Frequency rank | #36,739 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “rho” sits in English frequency
Spelling & Dictionary Insight
The English entry for rho is 3 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ɹəʊ/. Corpus data places it at rank #36,739 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.
We couldn't generate a plausible misspelling set for rho, typically a sign the spelling maps closely to how the word sounds. It also participates in 20 confusable-pair relationships, "RS", "RT", "RM", and more, since the words sound or look close enough that writers reach for the wrong one mid-sentence.
Etymologically, the entry records: From the name of the Ancient Greek letter ῥῶ (rhô). The correct English form is rho, spelled R-H-O.
Definition
- 1The seventeenth letter of the Modern Greek and Classical alphabets and the nineteenth letter of Old and Ancient.
- 2The sensitivity of the option value to the risk-free interest rate.
Etymology
From the name of the Ancient Greek letter ῥῶ (rhô).
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 “rho”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is R-H-O - every other letter order is a misspelling in standard orthography.
- Say it as /ɹəʊ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Don't mix it up with “RS” - see the side-by-side comparison. rho vs RS
- 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.