Passersby is the only correct plural form. Passerbys and passerbyers are both spelling errors.
They do not exist in standard English dictionaries and should never appear in formal or informal writing.
This guide breaks down the correct plural of passerby, why the spelling works the way it does, and how to use it confidently every time.
What Does Passerby Mean?
Passerby is a noun that describes a person who is walking past a place — someone who happens to be going by at a particular moment, usually without stopping.
It is a compound noun made up of two parts:
- Passer — the main noun, meaning someone who passes
- By — a preposition indicating movement past something
Example: “A passerby stopped to help the injured dog on the sidewalk.”
Common uses:
- Describing witnesses to an accident or event
- Referring to strangers walking past a location
- News reporting and eyewitness accounts
- Everyday descriptions of street scenes
Related Word Forms: Passerby
What Is the Plural of Passerby?
This is where most people make the mistake. The correct plural of passerby is passersby — not passerbys and not passerbyers.
Why “Passersby” — Not “Passerbys”?
English pluralizes compound nouns by adding -s to the main noun — not to the end of the whole word.
In passerby, the main noun is passer — the person doing the passing. The word by is just a preposition. So the plural attaches to passer — giving you passers-by or passersby.
Compound Nouns – Correct vs Incorrect Plurals
The pattern is consistent — pluralize the main noun, not the preposition or the end of the word.
Passersby or Passers-by — Which Is Correct?
Both are acceptable. Passersby (no hyphen) is the most widely used and modern form. Passers-by (hyphenated) is also correct and appears in many British and formal writing contexts.
Passersby – Correct Forms & Status
Why Do People Misspell It?
The most natural instinct is to add -s to the end of any word to make it plural. That works for most nouns — cat → cats, book → books, table → tables.
But passerby is a compound noun — and compound nouns follow different pluralization rules. The -s goes on the head noun (passer), not the tail of the full word.
Most people treat passerby as a single unit and write passerbys — logical by instinct, but grammatically wrong. Others overcorrect and invent passerbyers — adding -ers as if it were a verb-based word. Neither is correct.
The fix is simple: Find the main noun. Add -s there.
Passer + s + by = passersby ✅
How to Use Passersby Correctly
In Everyday Sentences
Passersby works as a standard plural noun — use it anywhere you would use a regular plural:
- “Several passersby witnessed the collision.”
- “The street performer attracted many passersby.”
- “Passersby were asked to avoid the area.”
In News and Formal Writing
Passersby appears frequently in journalism and eyewitness reporting:
- “According to passersby, the argument started outside the building.”
- “Passersby helped direct traffic until officers arrived.”
Common Mistakes to Avoid
Memory trick: Think of mothers-in-law — you would never say mother-in-laws. You pluralize the main person — the mother. Same rule applies here — pluralize the main person — the passer. Passersby every time.
FAQs — Passersby or Passerbys or Passerbyers
Which is correct, passersby or passerbys?
Passersby is always correct. Passerbys is a spelling error. The plural is formed by adding -s to the main noun passer — not to the end of the full word.
What is the plural form of a passerby?
The correct plural form is passersby — or passers-by with a hyphen. Both are acceptable. Passerbys and passerbyers are both incorrect and should be avoided.
How to use passersby?
Use passersby exactly as you would any plural noun. Example: “Several passersby stopped to watch the street musician perform.”
What is a passerby?
A passerby is a person who is walking or passing by a particular place — typically a stranger who happens to be present at a location without specifically intending to stop there.
Conclusion
The spelling rule here is clear and consistent. Passersby is the only correct plural of passerby — formed by pluralizing the main noun passer, not the end of the compound word. Passerbys and passerbyers are both errors with no place in standard English writing.
Remember the pattern — in compound nouns, the -s always goes on the head noun. Apply that rule to passerby and you get passersby every single time. Simple, logical, and always correct.
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