reactionvsreductionTell them apart

Which to use

“reaction” and “reduction” are a confusable French pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#30,770
“reaction” frequency rank
#30,773
“reduction” frequency rank
61543
confusion score

Side-by-Side Comparison

Feature reaction reduction
Definition Réaction. Réduction, diminution.

Where the eye mixes reaction and reduction

Muted = shared; highlighted = the visual trap. They share 7 letters in sequence.

8 ch
reaction
9 ch
reduction

Why the eye confuses reaction with reduction

A purely visual mix-up. reaction (\ɹiˈæk.ʃən\) and reduction (\ɹɪˈdʌk.ʃən\) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 61543, derived from the frequency rank of both members and their visual similarity.

reaction is recorded at frequency rank #30,770, classified as anoun, pronounced \ɹiˈæk.ʃən\. reduction is at rank #30,773, tagged as anoun, pronounced \ɹɪˈdʌk.ʃən\.

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 61543, this pair ranks #91,690 of 440,172 scored French confusable pairs - among the most confusable pairs.

Orthographic DNA of reaction vs reduction

Shared letters: ceinort. Private to "reaction": a. Private to "reduction": du.

"reaction" · 8 letters · shape CVVCCVVC  ·  "reduction" · 9 letters · shape CVCVCCVVC

Known mistypes of this pair

  • reactioneraction · raection · reacction · reaciton · reactino · reactionn · reactoin · reacttion
  • reductionerduction · rdeuction · redcution · redduction · reducction · reduciton · reductino · reductionn

Frequently Asked Questions

Is swapping "reaction" for "reduction" ever safe?
No. They are said differently (\ɹiˈæk.ʃən\ versus \ɹɪˈdʌk.ʃən\) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Which is more common, "reaction" or "reduction"?
"reaction" is the more common of the two: it sits at frequency rank #30,770 in our French list, against #30,773 for "reduction". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

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

  • Full dictionary entry for "reaction" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "reduction" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #91,690 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
  • "reaction" and "reduction" also get mixed up with nearby pairs, the highest-scored neighbour is "reaction vs réfraction". 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 #91,690 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list