passer-by

• passerby

passer +‎ by

passer-by (plural passers-by)

1. A person who is passing by (that is, walking past).
   • 1963, Margery Allingham, chapter 10, in The China Governess‎:

     With a little manœuvring they contrived to meet on the doorstep which was […] in a boiling stream of passers-by, hurrying business people speeding past in a flurry of fumes and dust in the bright haze.

   When he tripped and fell in the street, several kind passers-by helped him up.

• bypasser