OPECvsopusTell them apart

Quick tell: OPEC is a name, opus is a noun, so they fill different roles in a sentence.

Which to use

“OPEC” is a name and “opus” is a noun - they look or sound alike but fill different roles in a sentence.

#23,928
“OPEC” frequency rank
#23,619
“opus” frequency rank
47547
confusion score

Side-by-Side Comparison

Feature OPEC opus
Definition Acronym of Organization of Petroleum Exporting Countries. A work of music or set of works with a specified rank in an ordering of a composer's complete published works.

Where the eye mixes OPEC and opus

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
OPEC
4 ch
opus

Why the eye confuses OPEC with opus

These two trip readers on the page rather than in the ear: OPEC is /ˈəʊpɛk/ while opus is /ˈəʊpəs/. 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 (name vs noun), which is usually the fastest check. Our composite confusion score for this pair is 47547, derived from the frequency rank of both members and their visual similarity.

OPEC is recorded at frequency rank #23,928, classified as aname, pronounced /ˈəʊpɛk/. opus is at rank #23,619, tagged as anoun, pronounced /ˈəʊpəs/.

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 47547, this pair ranks #201,460 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of OPEC vs opus

Shared letters: op. Private to "OPEC": ce. Private to "opus": su.

"OPEC" · 4 letters · shape VCVC  ·  "opus" · 4 letters · shape VCVC

Known mistypes of this pair

  • OPECoepc · opce · opecc · oppec · poec
  • opusoppus · opsu · opuss · oups · pous

Frequently Asked Questions

Do "OPEC" and "opus" mean the same thing in a sentence?
No - they are not even the same part of speech. "OPEC" is a name and "opus" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "OPEC" or "opus" show up more?
"opus" is the more common of the two: it sits at frequency rank #23,619 in our English list, against #23,928 for "OPEC". 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 "OPEC" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "opus" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #201,460 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "OPEC" and "opus" also get mixed up with nearby pairs, the highest-scored neighbour is "opus vs OWS". 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 #201,460 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