Which to use
“caster” and “cotter” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #25,312
- “caster” frequency rank
- #37,401
- “cotter” frequency rank
- 62713
- confusion score
Side-by-Side Comparison
| Feature | caster | cotter |
|---|---|---|
| Definition | Someone or something that casts. | A pin or wedge inserted through a slot to hold machine parts together. |
Where the eye mixes caster and cotter
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.
Look-alike desk: caster vs cotter
A purely visual mix-up. caster (/ˈkɑːstə(ɹ)/) and cotter (/kɒtə/) 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 62713, derived from the frequency rank of both members and their visual similarity.
caster is recorded at frequency rank #25,312, classified as anoun, pronounced /ˈkɑːstə(ɹ)/. cotter is at rank #37,401, tagged as anoun, pronounced /kɒtə/.
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 62713, this pair ranks #86,943 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of caster vs cotter
Shared letters: cert. Private to "caster": as. Private to "cotter": o.
"caster" · 6 letters · shape CVCCVC · "cotter" · 6 letters · shape CVCCVC
Known mistypes of this pair
Frequently Asked Questions
Can "caster" and "cotter" be used interchangeably?
Which is more common, "caster" or "cotter"?
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 "caster" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "cotter" - compare definitions side by side with the headword page. Word entry
- This pair ranks #86,943 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "caster" and "cotter" also get mixed up with nearby pairs, the highest-scored neighbour is "cotter vs cower". 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 #86,943 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.