Which to use
“fast” is an adverb and “FSB” is a noun - they look or sound alike but fill different roles in a sentence.
- #243
- “fast” frequency rank
- #41,175
- “FSB” frequency rank
- 41418
- confusion score
Side-by-Side Comparison
| Feature | fast | FSB |
|---|---|---|
| Definition | nicht ganz | russischer Inlandsgeheimdienst und Geheimpolizei |
Where the eye mixes fast and FSB
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.
Look-alike desk: fast vs FSB
These two trip readers on the page rather than in the ear: fast is [fast] while FSB is [ɛfʔɛsˈbeː]. 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 (adverb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 41418, derived from the frequency rank of both members and their visual similarity.
fast is recorded at frequency rank #243, classified as anadv, pronounced [fast]. FSB is at rank #41,175, tagged as anoun, pronounced [ɛfʔɛsˈbeː].
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 41418, this pair ranks #1,480,035 of 2,006,359 scored German confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of fast vs FSB
Shared letters: fs. Private to "fast": at. Private to "FSB": b.
"fast" · 4 letters · shape CVCC · "FSB" · 3 letters · shape CCC
Known mistypes of this pair
- fast ← afst · fastt · fats · ffast · fsat
Frequently Asked Questions
Can "fast" and "FSB" be used interchangeably?
In ordinary German text, does "fast" or "FSB" show up more?
Useful next steps
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "fast" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "FSB" - compare definitions side by side with the headword page. Word entry
- This pair ranks #1,480,035 of 2,006,359 scored German confusable pairs in this corpus vintage. Corpus statistics
- "fast" and "FSB" also get mixed up with nearby pairs, the highest-scored neighbour is "fist vs FSB". 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 #1,480,035 of 2,006,359 scored German pairs, corpus vintage 2026-09-03, not spelling advice.