Which to use
“fifties” is a noun and “fiftieth” is an adjective - they look or sound alike but fill different roles in a sentence.
- #22,085
- “fifties” frequency rank
- #45,371
- “fiftieth” frequency rank
- 67456
- confusion score
Side-by-Side Comparison
| Feature | fifties | fiftieth |
|---|---|---|
| Definition | plural of fifty | The ordinal form of the number fifty. |
Where the eye mixes fifties and fiftieth
Muted = shared; highlighted = the visual trap. They share 6 letters in sequence. fifties runs 7 letters (CVCCVVC) against fiftieth's 8 (CVCCVVCC) - the length gap alone is often enough to separate them once you know to check it.
Visual trap between fifties and fiftieth
These two trip readers on the page rather than in the ear: fifties is /ˈfɪftiz/ while fiftieth is /ˈfɪf.ti.əθ/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (noun vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 67456, derived from the frequency rank of both members and their visual similarity.
fifties is recorded at frequency rank #22,085, classified as anoun, pronounced /ˈfɪftiz/. fiftieth is at rank #45,371, tagged as anadj, pronounced /ˈfɪf.ti.əθ/.
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 67456, this pair ranks #63,280 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of fifties vs fiftieth
Shared letters: efit. Private to "fifties": s. Private to "fiftieth": h.
"fifties" · 7 letters · shape CVCCVVC · "fiftieth" · 8 letters · shape CVCCVVCC
Known mistypes of this pair
Frequently Asked Questions
Can "fifties" and "fiftieth" be used interchangeably?
Which is more common, "fifties" or "fiftieth"?
What to do next
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "fifties" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "fiftieth" - compare definitions side by side with the headword page. Word entry
- This pair ranks #63,280 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "fifties" and "fiftieth" also get mixed up with nearby pairs, the highest-scored neighbour is "fifteenth vs fiftieth". 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 #63,280 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.