IC vs ill, What's the Difference?

Which to use

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

#13,931
“IC” frequency rank: #1,946
“ill” frequency rank: 15877
confusion score

Side-by-Side Comparison

Feature	IC	ill
Definition	Initialism of independent contractor.	Evil; wicked (of people).

Letter map: IC vs ill

Shared letters muted; letters that set IC and ill apart highlighted. Shared run: 1.

2 ch

3 ch

ill

Grammar separator: IC vs ill

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: IC is anoun and illanadjective. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 15877, derived from the frequency rank of both members and their visual similarity.

IC is recorded at frequency rank #13,931, classified as anoun. ill is at rank #1,946, 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 15877, this pair ranks #461,252 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of IC vs ill

Shared letters: i. Private to "IC": c. Private to "ill": l.

"IC" · 2 letters · shape VC · "ill" · 3 letters · shape VCC

Frequently Asked Questions

Is swapping "IC" for "ill" ever safe?

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

Frequency check: "IC" vs "ill" - which ranks higher?

"ill" is the more common of the two: it sits at frequency rank #1,946 in our English list, against #13,931 for "IC". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pair "IC" vs "ill" is on the table, pick a follow-up below.

Full dictionary entry for "IC" 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 #461,252 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"IC" and "ill" also get mixed up with nearby pairs, the highest-scored neighbour is "IC vs ith". Nearby pair

Confusion rank #461,252 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.