English grammar can feel confusing when a simple-looking word forms an unusual plural. One of the most misunderstood examples is passerby. Many learners are unsure whether the plural should be passersby, passerbyers, or passerbys.
This guide explains the meaning, correct plural, examples, rules, origin, usage, and simple memory tricks to help you remember it forever.
What Does “Passerby” Mean?
A passerby is someone who passes by a place—typically someone walking or traveling near a scene.
Examples:
- A passerby saw the accident and called for help.
- A passerby complimented her outfit.
It is widely used in daily conversations, news reports, and storytelling.
Passerbyers, Passersby, or Passerby: Which One Is Correct?
The correct plural form of passerby is passersby.
❌ Incorrect Forms
- passerbyers
- passerbies
- passerbys
✔ Correct Form
- passersby
This follows standard English rules for compound nouns.
Why “Passersby” Is Correct (Grammar Rule)
“Passerby” = passer (noun) + by (preposition)
English grammar rules say that the main noun receives the plural form.
So:
passer → passers
by → stays the same
→ passersby
Why “Passerbyers” Is Incorrect
Many learners incorrectly add -ers to the entire word (passerbyers), but this breaks the rule of compound nouns.
“By” never changes. Only the main noun changes.
Therefore:
passerbyers = wrong
passersby = correct
Examples of Passersby (Correct Plural Usage)
- Many passersby took photos of the parade.
- Several passersby gave witness statements to police.
- Curious passersby gathered around the street artist.
Examples of Passerby (Singular Usage)
- A passerby returned my lost wallet.
- The noise caught the attention of a passerby.
Passerby vs. Passersby (Comparison Table)
| Word | Type | Meaning | Example |
| Passerby | Singular | One person who passes by | A passerby reported the issue. |
| Passersby | Plural | More than one passerby | Passersby gathered at the scene. |
| Passerbyers | ❌ Wrong | Not used in English | — |
Is “Passerbyers” Used Informally?
No.
Even in casual speaking or texting, native speakers never use “passerbyers.” It is always incorrect.
Word Origin of “Passerby” (Etymology)
“Passerby” comes from:
- passer → someone who passes
- by → indicating movement past something
The plural passersby has been used since the late 1700s and remains standard in all English varieties.
Words Similar to “Passerby”
| Singular | Plural |
| hanger-on | hangers-on |
| runner-up | runners-up |
| mother-in-law | mothers-in-law |
| sister-in-law | sisters-in-law |
| passerby | passersby |
All follow the same pattern: Plural on the first word.
Common Mistakes People Make
| Wrong | Correct |
| passerbyers | passersby |
| passerbys | passersby |
| passerbies | passersby |
| passerby | passerby |
| passersbys | ❌ not a word |
Possessive Forms (Important for Writing)
Singular Possessive:
passerby’s
- The passerby’s phone fell on the road.
Plural Possessive:
passersby’s
- The passersby’s reactions were recorded.
How to Easily Remember the Plural “Passersby”
✔ Trick 1: Plural Goes on the Person
Who is plural? The people → passers
✔ Trick 2: Compare With Similar Words
If mothers-in-law works, then passersby works too.
✔ Trick 3: Split the Word
passer + by → passersby
Examples in News and Professional Writing
- “Three passersby rushed to assist the victim.”
- “Police reviewed the phones of passersby for evidence.”
All reputable publications use passersby.
American vs. British English Usage
There is no difference.
Both US and UK English use:
✔ passerby
✔ passersby
❌ passerbyers
How “Passersby” Is Used in Legal and Police Reports
The word passersby is very common in legal statements, police reports, and official investigations. Authorities often use it while describing eyewitnesses who were not directly involved in an incident but happened to be nearby. The word helps separate random witnesses from involved individuals. For example, in accident reports, police write: “Several passersby witnessed the collision and provided statements.”
This shows how the term helps identify people present without implying they were connected to the event.In legal writing, accuracy matters. Using passersby instead of incorrect forms like “passerbyers” ensures professionalism. Lawyers, journalists, and public officials rely on this correct plural to maintain credibility and clarity, especially when documenting evidence, interviews, or crime-scene interactions.
Common Confusion With Similar-Looking Words
Many English learners confuse passerby with similar constructions such as bystander, onlooker, and spectator. Although they appear in the same context, their meanings differ. A bystander refers to someone present but not involved, while a spectator is usually someone watching an event intentionally. A passerby, however, is someone who happened to pass near a situation without planning to stop or watch. This difference explains why passersby only describes accidental presence, not active observation.
Confusion also occurs with words like walkers, commuters, and travelers, but these are regular nouns with standard plural forms. “Passerby,” being a compound noun, does not follow those simple rules. Understanding these distinctions helps prevent mistakes and improves your writing accuracy.
When to Use Passerby vs. Bystander
Choosing between passerby and bystander depends on context. Use passerby when the person is simply moving past a location. For example, someone walking down the street who briefly notices a scene is a passerby. They were not there purposely; they were just passing. Use bystander when the person is present but not participating. For instance, in an emergency, a bystander may stand near the scene without helping, while a passerby may walk by and only notice it momentarily.
Writers often choose passersby in stories and news when describing people who witnessed something unexpectedly. This small difference can change the tone of your writing. “Bystanders watched the protest” sounds intentional, while “passersby watched the protest” implies they discovered it while passing.
Frequently Asked Questions
1. What is the correct plural of passerby?
The correct plural is passersby.
2. Is “passerbyers” grammatically allowed?
No. It is always incorrect.
3. Does “passerbys” exist?
No. Use passersby.
4. How do you use passerby in a sentence?
“A passerby called the police immediately.”
5. Why doesn’t the word end with ‘s’?
Because only the first noun (passer) takes the plural.
Conclusion
When choosing between passerbyers, passersby, and passerby, the only correct form is passersby. This follows English rules for compound nouns, where the plural appears on the primary noun and not the preposition.
Incorrect variations such as “passerbyers” and “passerbys” appear online but are never accepted in standard English. By remembering the rule “plural on the first word,” you can always write this term correctly.
