Which to use
“firm” and “firth” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #1,693
- “firm” frequency rank
- #22,972
- “firth” frequency rank
- 24665
- confusion score
Side-by-Side Comparison
| Feature | firm | firth |
|---|---|---|
| Definition | A business partnership; the name under which it trades. | An arm or inlet of the sea; a river estuary. |
Where the eye mixes firm and firth
Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.
Spelling & Dictionary Insight
A purely visual mix-up. firm (/fɜɹm/) and firth (/fɜːθ/) are said differently, so reading them aloud is the quickest way to catch the wrong one. On the page they stay close: they differ by 1 letter(s) in length. Our composite confusion score for this pair is 24665, derived from the frequency rank of both members and their visual similarity.
firm is recorded at frequency rank #1,693, classified as anoun, pronounced /fɜɹm/. firth is at rank #22,972, tagged as anoun, pronounced /fɜːθ/.
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 24665, this pair ranks #400,307 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.
Orthographic DNA of firm vs firth
Shared letters: fir. Private to "firm": m. Private to "firth": ht.
"firm" · 4 letters · shape CVCC · "firth" · 5 letters · shape CVCCC