Which to use
“mos” is an adverb and “must” is a noun - they look or sound alike but fill different roles in a sentence.
- #32,917
- “mos” frequency rank
- #16,189
- “must” frequency rank
- 49106
- confusion score
Side-by-Side Comparison
| Feature | mos | must |
|---|---|---|
| Definition | Ne … pas : négation à l'impératif, au subjonctif, après në « si » et duke « en ». | Devoir incontournable ; obligation sociale. |
Where the eye mixes mos and must
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Look-alike desk: mos vs must
These two trip readers on the page rather than in the ear: mos is \mos\ while must is \mœst\. 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 49106, derived from the frequency rank of both members and their visual similarity.
mos is recorded at frequency rank #32,917, classified as anadv, pronounced \mos\. must is at rank #16,189, tagged as anoun, pronounced \mœst\.
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 49106, this pair ranks #173,447 of 440,172 scored French confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of mos vs must
Shared letters: ms. Private to "mos": o. Private to "must": tu.
"mos" · 3 letters · shape CVC · "must" · 4 letters · shape CVCC
Known mistypes of this pair
- must ← mmust · msut · musst · mustt · muts · umst
Frequently Asked Questions
Is swapping "mos" for "must" ever safe?
Frequency check: "mos" vs "must" - which ranks higher?
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 "mos" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "must" - compare definitions side by side with the headword page. Word entry
- This pair ranks #173,447 of 440,172 scored French confusable pairs in this corpus vintage. Corpus statistics
- "mos" and "must" also get mixed up with nearby pairs, the highest-scored neighbour is "mos vs MWh". 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 #173,447 of 440,172 scored French pairs, corpus vintage 2026-09-03, not spelling advice.