IES vs ill, What's the Difference?

Which to use

“IES” is an abbrev and “ill” is an adjective - they look or sound alike but fill different roles in a sentence.

#21,019
“IES” frequency rank: #43,059
“ill” frequency rank: 64078
confusion score

Side-by-Side Comparison

Feature	IES	ill
Definition	Instituto de Educación Secundaria (España).	Enfermo.

Where the spellings diverge

Shared letters are muted; the letters that actually set IES and ill apart are highlighted. They share 1 letter in sequence, which is exactly why the eye skips the difference.

3 ch

IES

3 ch

ill

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: IES is [ˈjes] while ill is /ɪl/. 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 (abbrev vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 64078, derived from the frequency rank of both members and their visual similarity.

IES is recorded at frequency rank #21,019, classified as anabbrev, pronounced [ˈjes]. 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 64078, this pair ranks #46,685 of 323,831 scored Spanish confusable pairs - among the most confusable pairs.

Orthographic DNA of IES vs ill

Shared letters: i. Private to "IES": es. Private to "ill": l.

"IES" · 3 letters · shape VVC · "ill" · 3 letters · shape VCC

Frequency comparison

IES#21,019

ill#43,059

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "IES" and "ill" be used interchangeably?

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

Which is more common, "IES" or "ill"?

"IES" is the more common of the two: it sits at frequency rank #21,019 in our Spanish list, against #43,059 for "ill". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering IES vs ill

The fastest way to pick the right one every time.

Check the role first: if you need an abbrev, it's “IES”; for an adjective, it's “ill”.
See each word in full, definition, IPA, etymology and its other confusables. Full “IES” entry
Browse more pairs most likely to be confused. Most confusable