This is the 10095th most frequent Polish word.
bieg
Run; course; gear.
'Bieg' here refers to a competitive running event.
Zorganizowano bieg na 5 kilometrów.
A 5-kilometer run was organized.
'Bieg' refers to a gear in mechanical context, often for cars.
Muszę zmienić bieg w samochodzie.
I need to change the gear in the car.
'Bieg' metaphorically describes the course or flow.