infravsintroWhat's the difference?

Quick tell: infra is a adverb, intro is a noun, so they fill different roles in a sentence.

Which to use

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

#32,864
“infra” frequency rank
#9,487
“intro” frequency rank
42351
confusion score

Side-by-Side Comparison

Feature infra intro
Definition Discussed later. An introduction.

Where the eye mixes infra and intro

Muted = shared; highlighted = the visual trap. They share 3 letters in sequence. infra and intro follow the identical consonant-vowel pattern (VCCCV). Same shape at a glance is often the real trap, independent of shared letters.

5 ch
infra
5 ch
intro

Why the eye confuses infra with intro

These two trip readers on the page rather than in the ear: infra is /ˈɪn.fɹə/ while intro is /ˈɪntɹoʊ/. 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 (adverb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 42351, 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/. intro is at rank #9,487, tagged as anoun, pronounced /ˈɪntɹoʊ/.

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 42351, this pair ranks #250,027 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of infra vs intro

Shared letters: inr. Private to "infra": af. Private to "intro": ot.

"infra" · 5 letters · shape VCCCV  ·  "intro" · 5 letters · shape VCCCV

Known mistypes of this pair

  • infra ← ifnra · infar · inffra · infrra · innfra · inrfa · nifra
  • intro ← inntro · inrto · intor · intrro · inttro · itnro

Frequently Asked Questions

Do "infra" and "intro" mean the same thing in a sentence?
No - they are not even the same part of speech. "infra" is an adverb and "intro" a noun, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "infra" vs "intro" - which ranks higher?
"intro" is the more common of the two: it sits at frequency rank #9,487 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.

Useful next steps

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "infra" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "intro" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #250,027 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "infra" and "intro" also get mixed up with nearby pairs, the highest-scored neighbour is "infra vs inna". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #250,027 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