idovsillWhat's the difference?

Which to use

“ido” and “ill” are a confusable Spanish pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#1,216
“ido” frequency rank
#43,059
“ill” frequency rank
44275
confusion score

Side-by-Side Comparison

Feature ido ill
Definition Loco, falto de cordura. Enfermo.

Where the eye mixes ido and ill

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

3 ch
ido
3 ch
ill

Look-alike desk: ido vs ill

A purely visual mix-up. ido ([ˈið̞o]) and ill (/ɪl/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 44275, derived from the frequency rank of both members and their visual similarity.

ido is recorded at frequency rank #1,216, classified as anadj, pronounced [ˈið̞o]. ill is at rank #43,059, tagged as anadj, pronounced /ɪl/.

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 44275, this pair ranks #137,969 of 323,831 scored Spanish confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of ido vs ill

Shared letters: i. Private to "ido": do. Private to "ill": l.

"ido" · 3 letters · shape VCV  ·  "ill" · 3 letters · shape VCC

Frequently Asked Questions

Is swapping "ido" for "ill" ever safe?
No. They are said differently ([ˈið̞o] versus /ɪl/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "ido" vs "ill" - which ranks higher?
"ido" is the more common of the two: it sits at frequency rank #1,216 in our Spanish list, against #43,059 for "ill". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

What to do next

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "ido" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "ill" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #137,969 of 323,831 scored Spanish confusable pairs in this corpus vintage. Corpus statistics
  • "ido" and "ill" also get mixed up with nearby pairs, the highest-scored neighbour is "ill vs iza". Nearby pair

Confusion rank #137,969 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