passer-by

British  

noun

1. a person that is passing or going by, esp on foot

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Explanation

A passer-by is someone who just happens to walk past something. If you trip and spill the contents of your backpack on the sidewalk, a kind passer-by will probably stop and help you gather your things. If you witness a car accident while you're walking to school, you're a passer-by, and if you stroll past someone who's juggling flaming torches on the sidewalk, you're also a passer-by. Before the mid-sixteenth century, the now-obsolete passager had the same meaning. Today, passer-by is a fairly straightforward word ("one who passes by"); its only slightly confusing aspect being the plural form, which is passers-by.

Example Sentences

Her mother, Sarah Keeling, 45, and passer-by, Mark Ratcliffe, 67, both died after trying to save her.

From BBC • Jan. 16, 2026

A passer-by spoke to her, which she says saved her life.

From BBC • Nov. 28, 2025

But after a "venomous" comment from a passer-by, Ms Wiggins said she wanted to remind people of the tradition's backstory.

From BBC • Nov. 26, 2025

Mr Garner said the ambulance service discussed the incident but found no full report needed, after a passer-by gave the wrong-side-of-the-river address due to the app failing.

From BBC • Aug. 19, 2025

Somebody passing by used to be called a passer-by, and several of them were passers-by.

From "Woe Is I" by Patricia T. O'Conner

Related Words

• bystander
• observer
• witness