loovslumConfusable pair

Which to use

“loo” and “lum” are a confusable English pair: similar on the page, but distinct in meaning, check the gloss before you choose.

#19,636
“loo” frequency rank
#47,736
“lum” frequency rank
67372
confusion score

Side-by-Side Comparison

Feature loo lum
Definition A lavatory: a room used for urination and defecation. A chimney; also, the top part of a chimney.

Where the eye mixes loo and lum

Muted = shared; highlighted = the visual trap. They share 1 letter in sequence.

3 ch
loo
3 ch
lum

Why the eye confuses loo with lum

A purely visual mix-up. loo (/luː/) 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 67372, derived from the frequency rank of both members and their visual similarity.

loo is recorded at frequency rank #19,636, classified as anoun, pronounced /luː/. 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 67372, this pair ranks #63,608 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of loo vs lum

Shared letters: l. Private to "loo": o. Private to "lum": mu.

"loo" · 3 letters · shape CVV  ·  "lum" · 3 letters · shape CVC

Frequently Asked Questions

Is swapping "loo" for "lum" ever safe?
No. They are said differently (/luː/ versus /lʌm/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "loo" vs "lum" - which ranks higher?
"loo" is the more common of the two: it sits at frequency rank #19,636 in our English list, against #47,736 for "lum". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.

  • Full dictionary entry for "loo" 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 #63,608 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "loo" and "lum" also get mixed up with nearby pairs, the highest-scored neighbour is "LSC vs lum". Nearby pair

Confusion rank #63,608 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list