Which to use
“cas” is an adjective and “casks” is a noun - they look or sound alike but fill different roles in a sentence.
- #14,713
- “cas” frequency rank
- #41,038
- “casks” frequency rank
- 55751
- confusion score
Side-by-Side Comparison
| Feature | cas | casks |
|---|---|---|
| Definition | Abbreviation of casual. | plural of cask |
Where the eye mixes cas and casks
Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.
Why the eye confuses cas with casks
These two trip readers on the page rather than in the ear: cas is /kæʒ/ while casks is /kɑːsks/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “cas” sits inside “casks”, and the parts of speech differ too (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 55751, derived from the frequency rank of both members and their visual similarity.
cas is recorded at frequency rank #14,713, classified as anadj, pronounced /kæʒ/. casks is at rank #41,038, tagged as anoun, pronounced /kɑːsks/.
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 55751, this pair ranks #131,279 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of cas vs casks
Shared letters: acs. Private to "cas": -. Private to "casks": k.
"cas" · 3 letters · shape CVC · "casks" · 5 letters · shape CVCCC
Known mistypes of this pair
- casks ← acsks · cakss · caskks · caskss · cassks · ccasks · csaks
Frequently Asked Questions
Is swapping "cas" for "casks" ever safe?
Which is more common, "cas" or "casks"?
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 "cas" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "casks" - compare definitions side by side with the headword page. Word entry
- This pair ranks #131,279 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "cas" and "casks" also get mixed up with nearby pairs, the highest-scored neighbour is "casks vs cates". 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 #131,279 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.