lupinvslupusWhat's the difference?

Which to use

“lupin” and “lupus” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#34,579
“lupin” frequency rank
#22,427
“lupus” frequency rank
57006
confusion score

Side-by-Side Comparison

Feature lupin lupus
Definition Any member of the genus Lupinus in the family Fabaceae. Any of a number of autoimmune diseases, the most common of which is systemic lupus erythematosus.

Where the eye mixes lupin and lupus

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

5 ch
lupin
5 ch
lupus

Visual trap between lupin and lupus

A purely visual mix-up. lupin (/ˈluːpɪn/) and lupus (/ˈluːpəs/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 57006, derived from the frequency rank of both members and their visual similarity.

lupin is recorded at frequency rank #34,579, classified as anoun, pronounced /ˈluːpɪn/. lupus is at rank #22,427, tagged as anoun, pronounced /ˈluːpəs/.

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 57006, this pair ranks #122,218 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of lupin vs lupus

Shared letters: lpu. Private to "lupin": in. Private to "lupus": s.

"lupin" · 5 letters · shape CVCVC  ·  "lupus" · 5 letters · shape CVCVC

Known mistypes of this pair

  • lupin ← llupin · lpuin · luipn · lupinn · lupni · luppin · ulpin
  • lupus ← llupus · lpuus · luppus · lupsu · lupuss · luups · ulpus

Frequently Asked Questions

Can "lupin" and "lupus" be used interchangeably?
No. They are said differently (/ˈluːpɪn/ versus /ˈluːpəs/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "lupin" vs "lupus" - which ranks higher?
"lupus" is the more common of the two: it sits at frequency rank #22,427 in our English list, against #34,579 for "lupin". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "lupin" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "lupus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #122,218 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "lupin" and "lupus" also get mixed up with nearby pairs, the highest-scored neighbour is "Lucan vs lupin". 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 #122,218 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