Which to use
“fem” is a num and “fémur” is a noun - they look or sound alike but fill different roles in a sentence.
- #41,915
- “fem” frequency rank
- #35,524
- “fémur” frequency rank
- 77439
- confusion score
Side-by-Side Comparison
| Feature | fem | fémur |
|---|---|---|
| Definition | Cinco. | Hueso del muslo, articulado con la pelvis en la parte superior y con la rótula y la tibia en la inferior. Es el más largo del esqueleto humano. |
Where the eye mixes fem and fémur
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence. fem runs 3 letters (CVC) against fémur's 5 (CVCVC) - the length gap alone is often enough to separate them once you know to check it.
Why the eye confuses fem with fémur
These two trip readers on the page rather than in the ear: fem is [fɛmˀ] while fémur is [ˈfemuɾ]. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 letter(s) in length, and the parts of speech differ too (num vs noun), which is usually the fastest check. Our composite confusion score for this pair is 77439, derived from the frequency rank of both members and their visual similarity.
fem is recorded at frequency rank #41,915, classified as anum, pronounced [fɛmˀ]. fémur is at rank #35,524, tagged as anoun, pronounced [ˈfemuɾ].
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 77439, this pair ranks #16,009 of 323,831 scored Spanish confusable pairs - among the most confusable pairs.
Orthographic DNA of fem vs fémur
Shared letters: fm. Private to "fem": e. Private to "fémur": rué.
"fem" · 3 letters · shape CVC · "fémur" · 5 letters · shape CVCVC
Frequently Asked Questions
Is swapping "fem" for "fémur" ever safe?
Frequency check: "fem" vs "fémur" - which ranks higher?
After this comparison
Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.
- Full dictionary entry for "fem" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "fémur" - compare definitions side by side with the headword page. Word entry
- This pair ranks #16,009 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
- "fem" and "fémur" also get mixed up with nearby pairs, the highest-scored neighbour is "fem vs fuer". Nearby pair
Confusion rank #16,009 of 323,831 scored Spanish pairs, corpus vintage 2026-09-03, not spelling advice.