firth
/fɜːθ/
"firth" is a 5-letter English headword indexed on PlainSpell.
The verdict
“firth” has 7 generated spelling variants in the English index at frequency #22,972. The variants make it a useful spelling check.
- #22,972
- frequency rank, English
- 18,613
- “F” headwords
- 7
- tracked misspellings
- 20
- confusable pairs
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An arm or inlet of the sea; a river estuary.
Corpus desk
Index EN-firth · firth · English
firth · rank #22,972 · 7 variants · 20 confusables
- FREQ-MID #22,972
- LEN-MID 5 letters
- VOW-1 1 vowel
- CONFUS-HIGH 20 pairs
- VAR-MID 7 variants
- BOOK-DENSE 18,613
- PHOTO-FINISH fireball
Nearest frequency peer: fireball (-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 neighbourhood for “firth”
Lower corpus rank = more everyday usage (inverted bar length for readability)
- finesse
finesse
77,031 corpus weight
- fireball
fireball
77,030 corpus weight
- firth
firth
77,029 corpus weight
- flannel
flannel
77,028 corpus weight
- floss
floss
77,027 corpus weight
- foresee
foresee
77,026 corpus weight
What this shows Bars show where “firth” sits against the nearest ranked English headwords in the FrequencyWords band, not a reprint of letter-browse containment.
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 | firth |
| Language | English |
| Part of speech | Noun |
| IPA | /fɜːθ/ |
| Letters | 5 |
| Frequency rank | #22,972 |
| Misspellings tracked | 7 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Where “firth” sits in English frequency
A misspelling magnet
The generator records 7 spelling variants around firth (IPA /fɜːθ/), anoun. Corpus frequency is #22,972 among 18,613 “F” headwords. Dominant gloss: "An arm or inlet of the sea; a river estuary.".
Our generated misspelling index lists 7 likely wrong-spelling variants for firth, with forms such as "ffirth", "firht", and "firrth". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 20 confusable-pair relationships, "fit", "fish", "fort", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.
Etymologically, the entry records: Borrowed from Scots firth, furth, from Northern Middle English fyrth, from either or both of Old English ford and Old Norse fjǫrðr (“firth, fjord”), from Proto-Germanic *ferþu, *ferþuz (“inlet, fjord”), from Proto-Indo-European *pértus (“crossing”), from *p… The correct English form is firth, spelled F-I-R-T-H.
Definition
- 1An arm or inlet of the sea; a river estuary.
Recorded use
Wiktionary examplesThese source excerpts show how firth appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
The descent continues, still more steeply to Dundee (Tay Bridge), and approaching from the bridge itself this sharp descent gives the curious appearance that the station is below the level of the firth.
They drove on, every rise in the road lifting their sightline clear of the drystone dykes along the roadside, gifting glimpses of the firth and the islands, the blue peaks of Arran.
Etymology
Borrowed from Scots firth, furth, from Northern Middle English fyrth, from either or both of Old English ford and Old Norse fjǫrðr (“firth, fjord”), from Proto-Germanic *ferþu, *ferþuz (“inlet, fjord”), from Proto-Indo-European *pértus (“crossing”), from *per- (“to carry forth”) + *-tus (suffix forming action nouns from verb roots). The English word is a doublet of fjord, ford, port, and fjard.
This word in other languages
Common misspellings
Also misspelled as:
- ffirth
- firht
- firrth
- firthh
- firtth
- fitrh
- ifrth
Misspelling Pattern Breakdown
How far each generated variant is from the correct spelling of firth - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.
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.
PlainSpell is rendered directly from structured Wiktionary extracts and open word-frequency lists, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 6, 2026. Primary sources: Wiktionary (via kaikki.org) and FrequencyWords.
Frequently Asked Questions
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Similar English words by spelling shape
Same letter count and similar misspelling depth for "firth", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 5 letters (nearest by frequency rank).
Similar misspelling depth
Headwords with a similar count of attested misspellings (7 here; floor ≥5).
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.