IOCvsISCWhich spelling fits?

Which to use

“IOC” and “ISC” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#21,248
“IOC” frequency rank
#43,722
“ISC” frequency rank
64970
confusion score

Side-by-Side Comparison

Feature IOC ISC
Definition Initialism of International Olympic Committee. Initialism of Internet Systems Consortium.

Letter map: IOC vs ISC

Shared letters muted; letters that set IOC and ISC apart highlighted. Shared run: 2.

3 ch
IOC
3 ch
ISC

Corpus notes: IOC and ISC

IOC and ISC are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they differ by a single letter - o in “IOC” becomes s in “ISC”. Our composite confusion score for this pair is 64970, derived from the frequency rank of both members and their visual similarity.

IOC is recorded at frequency rank #21,248, classified as aname. ISC is at rank #43,722, tagged as aname.

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 64970, this pair ranks #75,082 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of IOC vs ISC

Shared letters: ci. Private to "IOC": o. Private to "ISC": s.

"IOC" · 3 letters · shape VVC  ·  "ISC" · 3 letters · shape VCC

Frequently Asked Questions

Can "IOC" and "ISC" be used interchangeably?
No. They differ by a single letter - o in “IOC” becomes s in “ISC”, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Which is more common, "IOC" or "ISC"?
"IOC" is the more common of the two: it sits at frequency rank #21,248 in our English list, against #43,722 for "ISC". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Done with this confusable. These links stay specific to "IOC" and "ISC".

  • Full dictionary entry for "IOC" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "ISC" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #75,082 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "IOC" and "ISC" also get mixed up with nearby pairs, the highest-scored neighbour is "ISC vs ith". Nearby pair

Confusion rank #75,082 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list