Which to use
“lac” and “lum” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.
- #19,379
- “lac” frequency rank
- #47,736
- “lum” frequency rank
- 67115
- confusion score
Side-by-Side Comparison
| Feature | lac | lum |
|---|---|---|
| Definition | A resinous substance or lacquer produced mainly on the banyan tree by the female of Kerria lacca, a scale insect. | A chimney; also, the top part of a chimney. |
Where the eye mixes lac and lum
Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.
Look-alike desk: lac vs lum
A purely visual mix-up. lac (/læk/) and lum (/lʌm/) 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 67115, derived from the frequency rank of both members and their visual similarity.
lac is recorded at frequency rank #19,379, classified as anoun, pronounced /læk/. lum is at rank #47,736, tagged as anoun, pronounced /lʌm/.
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 67115, this pair ranks #64,855 of 530,003 scored English confusable pairs - among the most confusable pairs.
Orthographic DNA of lac vs lum
Shared letters: l. Private to "lac": ac. Private to "lum": mu.
"lac" · 3 letters · shape CVC · "lum" · 3 letters · shape CVC
Frequently Asked Questions
Can "lac" and "lum" be used interchangeably?
Frequency check: "lac" vs "lum" - 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 "lac" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "lum" - compare definitions side by side with the headword page. Word entry
- This pair ranks #64,855 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "lac" and "lum" also get mixed up with nearby pairs, the highest-scored neighbour is "LSC vs lum". Nearby pair
Confusion rank #64,855 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.