im vs ion, What's the Difference?

Which to use

“im” is an adjective and “ion” is a noun - they look or sound alike but fill different roles in a sentence.

#10,152
“im” frequency rank: #22,745
“ion” frequency rank: 32897
confusion score

Side-by-Side Comparison

Feature	im	ion
Definition	Mi.	Partícula cargada eléctricamente constituida por un átomo o molécula que no es eléctricamente neutro.

Letter map: im vs ion

Shared letters muted; letters that set im and ion apart highlighted. Shared run: 1.

2 ch

3 ch

ion

Grammar separator: im vs ion

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: im is anadjective and ionanoun. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 32897, derived from the frequency rank of both members and their visual similarity.

im is recorded at frequency rank #10,152, classified as anadj. ion is at rank #22,745, tagged as anoun, pronounced [ˈjõn].

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 32897, this pair ranks #199,624 of 323,831 scored Spanish confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of im vs ion

Shared letters: i. Private to "im": m. Private to "ion": no.

"im" · 2 letters · shape VC · "ion" · 3 letters · shape VVC

Frequently Asked Questions

Is swapping "im" for "ion" ever safe?

No - they are not even the same part of speech. "im" is an adjective and "ion" a noun, so a sentence built for one is usually ungrammatical with the other.

In ordinary Spanish text, does "im" or "ion" show up more?

"im" is the more common of the two: it sits at frequency rank #10,152 in our Spanish list, against #22,745 for "ion". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

You've compared "im" and "ion". Here's where to go from here.

Full dictionary entry for "im" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "ion" - compare definitions side by side with the headword page. Word entry
This pair ranks #199,624 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
"im" and "ion" also get mixed up with nearby pairs, the highest-scored neighbour is "ion vs iza". Nearby pair

Confusion rank #199,624 of 323,831 scored Spanish pairs, corpus vintage 2026-09-03, not spelling advice.