flackvsflankTell them apart

Which to use

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

#30,799
“flack” frequency rank
#12,241
“flank” frequency rank
43040
confusion score

Side-by-Side Comparison

Feature flack flank
Definition To flutter; palpitate. To attack the flank(s) of.

Where the eye mixes flack and flank

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.

5 ch
flack
5 ch
flank

Why the eye confuses flack with flank

A purely visual mix-up. flack (/flæk/) and flank (/ˈflæŋk/) 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 a single letter - c in “flack” becomes n in “flank”. Our composite confusion score for this pair is 43040, derived from the frequency rank of both members and their visual similarity.

flack is recorded at frequency rank #30,799, classified as averb, pronounced /flæk/. flank is at rank #12,241, tagged as averb, pronounced /ˈflæŋk/.

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 43040, this pair ranks #243,758 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of flack vs flank

Shared letters: afkl. Private to "flack": c. Private to "flank": n.

"flack" · 5 letters · shape CCVCC  ·  "flank" · 5 letters · shape CCVCC

Known mistypes of this pair

  • flackfalck · fflack · flacck · flackk · flakc · flcak · fllack · lfack
  • flankfalnk · fflank · flakn · flankk · flannk · fllank · flnak · lfank

Frequently Asked Questions

Is swapping "flack" for "flank" ever safe?
No. They are said differently (/flæk/ versus /ˈflæŋk/) and carry different meanings; reading the sentence aloud is usually enough to catch the wrong one.
Frequency check: "flack" vs "flank" - which ranks higher?
"flank" is the more common of the two: it sits at frequency rank #12,241 in our English list, against #30,799 for "flack". 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 "flack" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "flank" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #243,758 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "flack" and "flank" also get mixed up with nearby pairs, the highest-scored neighbour is "flack vs flail". 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 #243,758 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