Which to use
“loco” is an adverb and “locum” is a noun - they look or sound alike but fill different roles in a sentence.
- #22,141
- “loco” frequency rank
- #47,732
- “locum” frequency rank
- 69873
- confusion score
Side-by-Side Comparison
| Feature | loco | locum |
|---|---|---|
| Definition | A direction in written or printed music to be returning to the proper pitch after having played an octave higher or lower. | Ellipsis of locum tenens. |
Where the eye mixes loco and locum
Muted = shared; highlighted = the visual trap. They share 3 letters in sequence. loco runs 4 letters (CVCV) against locum's 5 (CVCVC) - the length gap alone is often enough to separate them once you know to check it.
Visual trap between loco and locum
These two trip readers on the page rather than in the ear: loco is /ˈləʊ.kəʊ/ while locum is /ˈləʊkəm/. 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 (adverb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 69873, derived from the frequency rank of both members and their visual similarity.
loco is recorded at frequency rank #22,141, classified as anadv, pronounced /ˈləʊ.kəʊ/. locum is at rank #47,732, tagged as anoun, pronounced /ˈləʊkəm/.
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 69873, this pair ranks #52,778 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of loco vs locum
Shared letters: clo. Private to "loco": -. Private to "locum": mu.
"loco" · 4 letters · shape CVCV · "locum" · 5 letters · shape CVCVC
Known mistypes of this pair
Frequently Asked Questions
Can "loco" and "locum" be used interchangeably?
In ordinary English text, does "loco" or "locum" show up more?
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 "loco" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "locum" - compare definitions side by side with the headword page. Word entry
- This pair ranks #52,778 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "loco" and "locum" also get mixed up with nearby pairs, the highest-scored neighbour is "lockup vs locum". 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 #52,778 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.