uníanvsuniónWhich spelling fits?

Quick tell: unían is a verb, unión is a noun, so they fill different roles in a sentence.

Which to use

“unían” is a verb and “unión” is a noun - they look or sound alike but fill different roles in a sentence.

#36,867
“unían” frequency rank
#904
“unión” frequency rank
37771
confusion score

Side-by-Side Comparison

Feature unían unión
Definition Tercera persona del plural (ellos, ellas; ustedes, 2.ª persona) del pretérito imperfecto de indicativo de unir o de unirse. Acción y efecto de unir o unirse.

Where the eye mixes unían and unión

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence. unían and unión follow the identical consonant-vowel pattern (VCVVC). Same shape at a glance is often the real trap, independent of shared letters.

5 ch
unían
5 ch
unión

Visual trap between unían and unión

These two trip readers on the page rather than in the ear: unían is [uˈniãn] while unión is [uˈnjõn]. 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 (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 37771, derived from the frequency rank of both members and their visual similarity.

unían is recorded at frequency rank #36,867, classified as averb, pronounced [uˈniãn]. unión is at rank #904, tagged as anoun, pronounced [uˈnjõn].

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 37771, this pair ranks #173,573 of 323,831 scored Spanish confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of unían vs unión

Shared letters: nu. Private to "unían": aí. Private to "unión": ió.

"unían" · 5 letters · shape VCVVC  ·  "unión" · 5 letters · shape VCVVC

Frequently Asked Questions

Do "unían" and "unión" mean the same thing in a sentence?
No - they are not even the same part of speech. "unían" is a verb and "unión" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "unían" or "unión"?
"unión" is the more common of the two: it sits at frequency rank #904 in our Spanish list, against #36,867 for "unían". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

After this comparison

Eye-level mix-up between "unían" and "unión" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "unían" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "unión" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #173,573 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
  • "unían" and "unión" also get mixed up with nearby pairs, the highest-scored neighbour is "uan vs unían". Nearby pair

Confusion rank #173,573 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