Which to use
“false” is an adjective and “flue” is a noun - they look or sound alike but fill different roles in a sentence.
- #2,345
- “false” frequency rank
- #38,401
- “flue” frequency rank
- 40746
- confusion score
Side-by-Side Comparison
| Feature | false | flue |
|---|---|---|
| Definition | Untrue, not factual, factually incorrect. | A pipe or duct that carries gaseous combustion products away from the point of combustion (such as a furnace). |
Where the eye mixes false and flue
Muted = shared; highlighted = the visual trap. They share 3 letters in sequence.
Why the eye confuses false with flue
These two trip readers on the page rather than in the ear: false is /fɔːls/ while flue is /fluː/. Spoken aloud the problem disappears. In writing it persists, because they differ by 1 letter(s) in length, and the parts of speech differ too (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 40746, derived from the frequency rank of both members and their visual similarity.
false is recorded at frequency rank #2,345, classified as anadj, pronounced /fɔːls/. flue is at rank #38,401, tagged as anoun, pronounced /fluː/.
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 40746, this pair ranks #264,758 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of false vs flue
Shared letters: efl. Private to "false": as. Private to "flue": u.
"false" · 5 letters · shape CVCCV · "flue" · 4 letters · shape CCVV
Known mistypes of this pair
Frequently Asked Questions
Is swapping "false" for "flue" ever safe?
Frequency check: "false" vs "flue" - which ranks higher?
What to do next
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "false" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "flue" - compare definitions side by side with the headword page. Word entry
- This pair ranks #264,758 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "false" and "flue" also get mixed up with nearby pairs, the highest-scored neighbour is "flue vs fou". 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 #264,758 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.