Noun
a person who passes by casually or by chance
Source: WordNetWith madness, as with vomit, it's the passerby who receives the inconvenience. Joe Orton
The referee told me this league has never had a brawl of that magnitude," said Mr. Penderwick after a long, painful silence. "Of course, at the time I was pretending to be a casual passerby and not a father at all. Jeanne Birdsall
[Ira Gershwin] said that [P.G.] Wodehouse will address a letter, stamp it and throw it out of his third-story window onto the street trusting in the good nature of passerby to pick it up and mail it. Oscar Levant
Now I was just a transient in the valley, a one-eyed passerby too fat for his years, and life there had the power to summon up neither the memory nor the illusion of any other, truer self. As a passerby I had a right to insist on my identity. Kenzaburō Ōe
A child's life is like a piece of paper on which every passerby leaves a mark. Chinese Proverb
“A fire can ravage buildings in mere minutes, putting every occupant or passerby at risk of serious injury or death. Source: Internet