infra vs IRA, What's the Difference?

Which to use

“infra” is an adverb and “IRA” is a noun - they look or sound alike but fill different roles in a sentence.

#32,864
“infra” frequency rank: #9,057
“IRA” frequency rank: 41921
confusion score

Side-by-Side Comparison

Feature	infra	IRA
Definition	Discussed later.	Initialism of individual retirement account.

Where the spellings diverge

Shared letters are muted; the letters that actually set infra and IRA apart are highlighted. They share 3 letters in sequence, which is exactly why the eye skips the difference.

5 ch

infra

3 ch

IRA

Spelling & Dictionary Insight

These two trip readers on the page rather than in the ear: infra is /ˈɪn.fɹə/ while IRA is /aɪ ɑɹ eɪ/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 letter(s) in length, and the parts of speech differ too (adverb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 41921, derived from the frequency rank of both members and their visual similarity.

infra is recorded at frequency rank #32,864, classified as anadv, pronounced /ˈɪn.fɹə/. IRA is at rank #9,057, tagged as anoun, pronounced /aɪ ɑɹ eɪ/.

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 41921, this pair ranks #253,925 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of infra vs IRA

Shared letters: air. Private to "infra": fn. Private to "IRA": -.

"infra" · 5 letters · shape VCCCV · "IRA" · 3 letters · shape VCV

Known mistypes of this pair

infra ← ifnra · infar · inffra · infrra · innfra · inrfa · nifra

Frequency comparison

infra#32,864

IRA#9,057

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "infra" and "IRA" be used interchangeably?

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

Which is more common, "infra" or "IRA"?

"IRA" is the more common of the two: it sits at frequency rank #9,057 in our English list, against #32,864 for "infra". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Remembering infra vs IRA

The fastest way to pick the right one every time.

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