Passersby or Passerbyers can seem tricky in everyday English, but passersby is the correct plural of passerby in standard English and writing. When choosing the right words, learners may find Passerbyers, Passersby, and Passerby confusing because they can sound alike and have irregular forms.
I’ve often hesitated when writing or saying this phrase, but the correct grammar and proper usage are clear: passerby is singular, while passersby is plural. This rule is essential for speaking and writing clearly, especially in formal and casual contexts.
The debate can spark among learners trying to master common mistakes, but simple language rules provide the answer. Real-life examples make the point clear: Several passersby saw an accident.
Quick Answer
Passersby is the correct plural of passerby in standard US English.
Here’s the basic rule:
- One person: a passerby
- Two or more people: passersby
- Incorrect: passerbyers
- Incorrect: passerbys
- Hyphenated variant: passer-by / passers-by
Examples
A passerby noticed the broken window.
Several passersby stopped to watch the performance.
Police asked the passersby whether they had seen the accident.
The important detail is where the plural changes. The word doesn’t become passerby + s. Instead, passer becomes passers, while by stays unchanged.
So:
passerby → passersby
Not:
passerby → passerbys
And definitely not:
passerby → passerbyers
Comparison Overview
The easiest way to understand the different forms is to compare them directly.
| Form | Correct in standard English? | Use |
| passerby | Yes | Singular |
| passersby | Yes | Plural |
| passer-by | Yes | Hyphenated singular variant |
| passers-by | Yes | Hyphenated plural variant |
| passerbys | No | Incorrect plural formation |
| passerbyers | No | Incorrect plural formation |
For US English, passerby and passersby are generally the most useful forms to choose.
British English sources also recognize the hyphenated forms passer-by and passers-by. The difference is primarily one of spelling and editorial convention rather than meaning.
At a glance
If you’re writing in American English and need the plural, use:
passersby
If you’re referring to one person, use:
passerby
That simple distinction covers most everyday situations.
Main Differences Between Passersby or Passerbyers
The biggest difference is that passersby is an established plural form, while passerbyers is not the standard plural of passerby.
The two forms might look as though they follow similar logic, but they don’t.
Why Passersby Is Correct
The word passerby is a compound noun. It combines passer, meaning a person who passes, with by, which indicates movement past a place or person.
When the noun becomes plural, English pluralizes passer:
passer + by
becomes
passers + by
The result is:
passersby
This pattern isn’t unique to passerby. English has several compound nouns where the plural marker appears inside the expression rather than at the very end.
Consider:
- runner-up → runners-up
- mother-in-law → mothers-in-law
- commander-in-chief → commanders-in-chief
- passerby → passersby
The pattern becomes much less mysterious once you stop treating passerby as an ordinary one-piece noun.
Why Passerbyers Is Incorrect
Passerbyers looks tempting because English frequently uses -er to describe someone who performs an action.
For example:
- run → runner
- teach → teacher
- work → worker
- drive → driver
A person who passes can indeed be called a passer. However, passerby already contains that noun.
The word doesn’t need another -er ending.
In other words, passerbyers incorrectly treats passerby as though it needs to become a new agent noun before it can be pluralized.
The correct structure is much simpler:
passer + by → passerby
Then:
passer + s + by → passersby
Adding -er again creates a form that doesn’t belong to the standard English plural system for this noun.
What Does Passerby Mean?
A passerby is a person who happens to pass a particular place or situation.
The word often describes someone who isn’t directly involved in what’s happening. They happen to be nearby while moving through an area.
For example:
A passerby saw smoke coming from the building.
The person wasn’t necessarily inside the building or involved with the incident. They simply happened to be passing when they noticed the smoke.
Similarly:
A passerby stopped to help the injured cyclist.
Here, the person’s defining connection to the event is that they were passing by when they encountered it.
Passerby as a Singular Noun
Use passerby when referring to one person.
Correct:
A passerby called the police.
Incorrect:
A passersby called the police.
The second sentence combines a singular article, a, with a plural noun.
You can test the form by replacing passerby with an ordinary singular noun:
A person called the police.
Therefore:
A passerby called the police.
Passersby as a Plural Noun
Use passersby when referring to more than one person.
Correct:
Several passersby called the police.
Correct:
The passersby gathered near the entrance.
Incorrect:
Several passerby called the police.
The word following several, many, numerous, or a plural number normally needs to be plural.
For example:
- one passerby
- two passersby
- several passersby
- many passersby
- dozens of passersby
Why Is the Plural of Passerby Passersby?
The answer lies in how English handles compound nouns.
A compound noun combines two or more words to create a noun with a specific meaning. In passerby, passer identifies the person and by describes the person’s relationship to the place or situation.
When the number changes, the noun portion takes the plural marker.
The Word Structure
Think of the word this way:
passer + by
Singular:
passerby
Plural:
passers + by
Therefore:
passersby
The word by doesn’t become plural. The person represented by passer does.
This is why passerbys doesn’t follow the standard pattern.
A Useful Comparison
The same principle appears in other compound nouns.
| Singular | Plural |
| runner-up | runners-up |
| mother-in-law | mothers-in-law |
| attorney general | attorneys general |
| passerby | passersby |
The exact grammatical history of each compound differs, but the practical lesson is similar: the plural marker doesn’t always appear at the end of a compound noun.
Is Passerbys Correct?
No. Passerbys is not the standard plural form.
It’s understandable why people write it. Most regular English nouns take the plural ending at the end:
- table → tables
- street → streets
- visitor → visitors
- pedestrian → pedestrians
Following that familiar pattern might lead someone to write:
passerby → passerbys
However, passerby uses an irregular compound plural pattern. The accepted standard form is:
passerby → passersby
Why Passerbys Looks Plausible
The spelling can look logical because by appears to be the final part of the word.
If someone thinks of passerby as one indivisible word, adding -s to the end seems natural.
English doesn’t always work that way with compounds.
Compare:
runner-up → runners-up
You wouldn’t normally write runner-ups in standard usage when referring to multiple runners-up.
Likewise:
passerby → passersby
The plural marker belongs with passer.
Is Passers-by Correct?
Yes. Passers-by is an established hyphenated plural form.
The spelling you’ll encounter depends partly on the variety of English and the dictionary or style guide being followed.
In contemporary US English, passerby and passersby are the straightforward forms to use. British English also commonly uses the hyphenated forms passer-by and passers-by.
For example:
Several passers-by stopped to watch.
This is a legitimate form, not a spelling mistake.
Passersby vs. Passers-by
| Form | Typical use |
| passerby | Standard closed singular form in US English |
| passersby | Standard closed plural form in US English |
| passer-by | Hyphenated singular variant |
| passers-by | Hyphenated plural variant |
The important point is consistency.
If your publication uses a particular house style, follow it. If you’re writing ordinary American English without a specific style requirement, passerby and passersby are clear and widely accepted choices.
Correct Examples of Passersby in Sentences
Seeing the word in context is often more useful than memorizing a rule.
Passersby as the Subject
Several passersby stopped when they heard the alarm.
Curious passersby gathered outside the theater.
Two passersby helped move the damaged bicycle from the road.
In each example, passersby refers to multiple people who happened to be passing.
Passersby as the Object
The street performer attracted dozens of passersby.
Volunteers asked passersby to answer a short survey.
The unusual sculpture caught the attention of nearby passersby.
Here, the word receives the action rather than performing it.
Passersby in News Writing
The word frequently appears in news reports because witnesses often happen to be people who were passing the scene.
For example:
Several passersby reported the fire after noticing smoke above the building.
This construction sounds natural because the people didn’t necessarily have a direct connection to the event.
Passersby in Research
Researchers may also use the term when describing people encountered in public spaces.
For example:
Researchers surveyed passersby outside the train station.
The term works particularly well when researchers recruit people based on their presence in a specific location rather than an existing relationship with the researchers.
Passerby vs. Bystander: What’s the Difference?
Passerby and bystander overlap, but they aren’t exact synonyms.
A passerby is defined by movement past a place.
A bystander is defined more by being present as an observer, particularly during an event.
Consider this example:
A passerby saw the collision and stopped.
The word passerby tells us how the person came to be there.
Now consider:
Several bystanders watched the collision.
The word bystanders focuses on their presence and observation.
A person can be both.
Someone walking down the street may become a bystander after stopping to watch an accident. Before stopping, that person was simply a passerby.
Passerby vs. Pedestrian
Pedestrian has another slightly different meaning.
A pedestrian is generally a person traveling on foot, especially in relation to traffic or public roads.
A passerby doesn’t have to be described primarily as a pedestrian. The word focuses on passing a particular location or situation.
For example:
A pedestrian crossed the road.
This emphasizes transportation or movement on foot.
A passerby noticed the broken streetlight.
This emphasizes the person’s incidental presence.
The same individual could fit both descriptions, but the words highlight different facts.
Read More: At the House vs. In the House: What’s the Difference?
The Possessive Form of Passersby
The possessive form can cause another round of confusion.
When something belongs to or is associated with one passerby, use:
passerby’s
Example:
The passerby’s account helped investigators understand what happened.
When something is associated with multiple passersby, use:
passersby’s
Example:
The passersby’s accounts differed on several details.
Notice something important: passersby already contains the plural marker. The possessive apostrophe-and-s construction comes afterward.
Singular and Plural Possessives
| Number | Form | Example |
| Singular | passerby’s | The passerby’s phone was found nearby. |
| Plural | passersby’s | The passersby’s statements were recorded. |
This may look unusual, but the same general idea applies to other irregular plurals.
The apostrophe belongs to the complete plural noun when you’re forming its possessive.
Common Mistakes With Passerby
Several errors appear repeatedly because writers try to apply the regular plural rule.
Mistake: Passerbyers
Incorrect: Several passerbyers stopped.
Correct: Several passersby stopped.
The standard plural doesn’t add -ers to the end.
Mistake: Passerbys
Incorrect: The store attracted many passerbys.
Correct: The store attracted many passersby.
The plural marker doesn’t go after by.
Mistake: One Passersby
Incorrect: One passersby reported the incident.
Correct: One passerby reported the incident.
The word one requires a singular noun.
Mistake: Two Passerby
Incorrect: Two passerby reported the incident.
Correct: Two passersby reported the incident.
A number greater than one requires the plural form.
Mistake: Mixing Hyphenated and Closed Forms
Avoid unnecessary inconsistency such as:
Several passers-by walked past the store while another passerby entered.
This isn’t necessarily grammatically impossible, but inconsistent spelling within the same piece can look careless.
Choose the form appropriate for your audience and style guide, then use it consistently.
FAQs:
Is “Passersby” the correct plural of “Passerby”?
Yes. Passersby is the standard and correct plural form of passerby. For example, “Several passersby stopped to help.”
Is “Passerbyers” a correct word?
No. Passerbyers is not the standard plural of passerby. Adding -ers creates an incorrect form. Use passersby instead.
Can I write “Passerbys” instead of “Passersby”?
No. Passerbys is generally considered incorrect in standard English. The plural changes passer to passers, while by remains unchanged.
Why does “Passerby” become “Passersby”?
Passerby is a compound word, so its plural form follows the main noun. Passer becomes passers, and by stays the same, producing passersby.
Should I use “Passersby” in formal writing?
Yes. Passersby is appropriate in both formal and casual writing. It’s the standard plural form and is suitable for articles, emails, reports, academic writing, and everyday communication.
Conclusion:
The correct plural of passerby is passersby, not passerbyers or passerbys. The change happens in the main noun passer, while by remains unchanged. Once you remember this pattern, you can confidently use passersby in both formal and casual English.
