rex
/ˈɹɛks/
"rex" is a 3-letter English headword indexed on PlainSpell.
The verdict
“rex” is a regularly-used English word, ranked #8,478 in English word frequency and used as a noun.
- #8,478
- frequency rank, English
- 3
- letters
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A king, particularly in ancient Rome.
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 | rex |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈɹɛks/ |
| Letters | 3 |
| Frequency rank | #8,478 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “rex” sits in English frequency
Spelling & Dictionary Insight
The English entry for rex is 3 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈɹɛks/. Corpus data places it at rank #8,478 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.
We couldn't generate a plausible misspelling set for rex, 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 Latin rēx (“king”), referring originally to rabbits of the Belgian "castorrex" breed, so named because their fur was similar to that of beavers. Entered English around 1920. Doublet of rajah and roy. The correct English form is rex, spelled R-E-X.
Definition
- 1A king, particularly in ancient Rome.
- 2An animal which has a genetic recessive variation that causes the guard hairs to be very short or fully lacking.
Etymology
From Latin rēx (“king”), referring originally to rabbits of the Belgian "castorrex" breed, so named because their fur was similar to that of beavers. Entered English around 1920. Doublet of rajah and roy.
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 “rex”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is R-E-X - every other letter order is a misspelling in standard orthography.
- Say it as /ˈɹɛks/ (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. rex 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.