IAS vs iz, What's the Difference?

Which to use

“IAS” is a noun and “iz” is a verb - they look or sound alike but fill different roles in a sentence.

#31,214
“IAS” frequency rank: #32,457
“iz” frequency rank: 63671
confusion score

Side-by-Side Comparison

Feature	IAS	iz
Definition	Initialism of indicated airspeed.	third-person singular simple present indicative of be

Letter map: IAS vs iz

Shared letters muted; letters that set IAS and iz apart highlighted. Shared run: 1. IAS runs 3 letters (VVC) against iz's 2 (VC) - the length gap alone is often enough to separate them once you know to check it.

3 ch

IAS

2 ch

Grammar separator: IAS vs iz

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: IAS is anoun and izaverb. On the page they differ by 1 letter(s) in length. Our composite confusion score for this pair is 63671, derived from the frequency rank of both members and their visual similarity.

IAS is recorded at frequency rank #31,214, classified as anoun. iz is at rank #32,457, tagged as averb.

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 63671, this pair ranks #81,709 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of IAS vs iz

Shared letters: i. Private to "IAS": as. Private to "iz": z.

"IAS" · 3 letters · shape VVC · "iz" · 2 letters · shape VC

Frequently Asked Questions

Can "IAS" and "iz" be used interchangeably?

No - they are not even the same part of speech. "IAS" is a noun and "iz" a verb, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "IAS" or "iz"?

"IAS" is the more common of the two: it sits at frequency rank #31,214 in our English list, against #32,457 for "iz". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pair "IAS" vs "iz" is on the table, pick a follow-up below.

Full dictionary entry for "IAS" with definition, IPA, and generated misspellings. Word entry
Full dictionary entry for "iz" - compare definitions side by side with the headword page. Word entry
This pair ranks #81,709 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
"IAS" and "iz" also get mixed up with nearby pairs, the highest-scored neighbour is "ith vs iz". Nearby pair

Confusion rank #81,709 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.