fluvsfoiWhat's the difference?

Which to use

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

#7,564
“flu” frequency rank
#42,644
“foi” frequency rank
50208
confusion score

Side-by-Side Comparison

Feature flu foi
Definition Influenza. A depiction of a handshake.

Letter map: flu vs foi

Shared letters muted; letters that set flu and foi apart highlighted. Shared run: 1.

3 ch
flu
3 ch
foi

Corpus notes: flu and foi

flu and foi are indexed as a confusable English pair. We have no recorded pronunciation or part of speech for both members, so the spelling overlap is what we can show you: they share most of their letters but differ in 2 positions. Our composite confusion score for this pair is 50208, derived from the frequency rank of both members and their visual similarity.

flu is recorded at frequency rank #7,564, classified as anoun, pronounced /fluː/. foi is at rank #42,644, tagged as anoun.

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 50208, this pair ranks #176,334 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of flu vs foi

Shared letters: f. Private to "flu": lu. Private to "foi": io.

"flu" · 3 letters · shape CCV  ·  "foi" · 3 letters · shape CVV

Frequently Asked Questions

Do "flu" and "foi" mean the same thing in a sentence?
No. They share most of their letters but differ in 2 positions, but the dictionary glosses above give them different meanings, so swapping one for the other changes what the sentence says.
Frequency check: "flu" vs "foi" - which ranks higher?
"flu" is the more common of the two: it sits at frequency rank #7,564 in our English list, against #42,644 for "foi". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

What to do next

Pair "flu" vs "foi" is on the table, pick a follow-up below.

  • Full dictionary entry for "flu" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "foi" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #176,334 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "flu" and "foi" also get mixed up with nearby pairs, the highest-scored neighbour is "foi vs FOMO". Nearby pair

Confusion rank #176,334 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