Which to use
“nuclear” is an adjective and “nuclei” is a noun - they look or sound alike but fill different roles in a sentence.
- #1,911
- “nuclear” frequency rank
- #22,751
- “nuclei” frequency rank
- 24662
- confusion score
Side-by-Side Comparison
| Feature | nuclear | nuclei |
|---|---|---|
| Definition | Pertaining to the nucleus of an atom. | plural of nucleus |
Where the eye mixes nuclear and nuclei
Muted = shared; highlighted = the visual trap. They share 5 letters in sequence. nuclear runs 7 letters (CVCCVVC) against nuclei's 6 (CVCCVV) - the length gap alone is often enough to separate them once you know to check it.
Visual trap between nuclear and nuclei
These two trip readers on the page rather than in the ear: nuclear is /ˈn(j)u.kli.ɚ/ while nuclei is /ˈnjuː.kli.aɪ/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 24662, derived from the frequency rank of both members and their visual similarity.
nuclear is recorded at frequency rank #1,911, classified as anadj, pronounced /ˈn(j)u.kli.ɚ/. nuclei is at rank #22,751, tagged as anoun, pronounced /ˈnjuː.kli.aɪ/.
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 24662, this pair ranks #400,336 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of nuclear vs nuclei
Shared letters: celnu. Private to "nuclear": ar. Private to "nuclei": i.
"nuclear" · 7 letters · shape CVCCVVC · "nuclei" · 6 letters · shape CVCCVV
Known mistypes of this pair
Frequently Asked Questions
Is swapping "nuclear" for "nuclei" ever safe?
Which is more common, "nuclear" or "nuclei"?
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 "nuclear" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "nuclei" - compare definitions side by side with the headword page. Word entry
- This pair ranks #400,336 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "nuclear" and "nuclei" also get mixed up with nearby pairs, the highest-scored neighbour is "nuclei vs nucleic". 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 #400,336 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.