This is the 3470th most frequent Swedish word.
bussarna
"The buses."
The plural definite form 'bussarna' refers to specific buses that the speaker observed arriving at the station.
Jag såg bussarna när de kom till stationen.
I saw the buses when they arrived at the station.
Here, 'bussarna' again represents multiple specific buses that are about to transport the children.
Barnen väntade på bussarna för att åka hem.
The children waited for the buses to go home.
The use of 'bussarna' indicates specific buses that are scheduled or expected.