Which to use
“fifth” is an adjective and “filth” is a noun - they look or sound alike but fill different roles in a sentence.
- #1,719
- “fifth” frequency rank
- #16,914
- “filth” frequency rank
- 18633
- confusion score
Side-by-Side Comparison
| Feature | fifth | filth |
|---|---|---|
| Definition | The ordinal form of the number five. | Dirt; foul matter; that which soils or defiles. |
Where the eye mixes fifth and filth
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.
Look-alike desk: fifth vs filth
These two trip readers on the page rather than in the ear: fifth is /fɪfθ/ while filth is /fɪlθ/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - f in “fifth” becomes l in “filth”, and the parts of speech differ too (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 18633, derived from the frequency rank of both members and their visual similarity.
fifth is recorded at frequency rank #1,719, classified as anadj, pronounced /fɪfθ/. filth is at rank #16,914, tagged as anoun, pronounced /fɪlθ/.
Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.
With a confusion score of 18633, this pair ranks #443,605 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of fifth vs filth
Shared letters: fhit. Private to "fifth": -. Private to "filth": l.
"fifth" · 5 letters · shape CVCCC · "filth" · 5 letters · shape CVCCC
Known mistypes of this pair
Frequently Asked Questions
Can "fifth" and "filth" be used interchangeably?
Which is more common, "fifth" or "filth"?
What to do next
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "fifth" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "filth" - compare definitions side by side with the headword page. Word entry
- This pair ranks #443,605 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "fifth" and "filth" also get mixed up with nearby pairs, the highest-scored neighbour is "filth vs frith". Nearby pair
- Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes
Confusion rank #443,605 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.