femvsfioWhich spelling fits?

Quick tell: fem is a num, fio is a verb, so they fill different roles in a sentence.

Which to use

“fem” is a num and “fio” is a verb - they look or sound alike but fill different roles in a sentence.

#41,915
“fem” frequency rank
#33,129
“fio” frequency rank
75044
confusion score

Side-by-Side Comparison

Feature fem fio
Definition Cinco. Tercera persona del singular (él, ella, ello; usted, 2.ª persona) del pretérito perfecto simple de indicativo de fiar.

Where the eye mixes fem and fio

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence. fem (CVC) and fio (CVV) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.

3 ch
fem
3 ch
fio

Visual trap between fem and fio

These two trip readers on the page rather than in the ear: fem is [fɛmˀ] while fio is [ˈfjo]. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (num vs verb), which is usually the fastest check. Our composite confusion score for this pair is 75044, 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]. fio is at rank #33,129, tagged as averb, pronounced [ˈfjo].

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 75044, this pair ranks #20,295 of 323,831 scored Spanish confusable pairs - among the most confusable pairs.

Orthographic DNA of fem vs fio

Shared letters: f. Private to "fem": em. Private to "fio": io.

"fem" · 3 letters · shape CVC  ·  "fio" · 3 letters · shape CVV

Frequently Asked Questions

Is swapping "fem" for "fio" ever safe?
No - they are not even the same part of speech. "fem" is a num and "fio" a verb, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "fem" or "fio"?
"fio" is the more common of the two: it sits at frequency rank #33,129 in our Spanish list, against #41,915 for "fem". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

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 "fio" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #20,295 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
  • "fem" and "fio" also get mixed up with nearby pairs, the highest-scored neighbour is "fem vs fuer". Nearby pair

Confusion rank #20,295 of 323,831 scored Spanish pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list