This is the 1662nd most frequent German word.
autobahn
A high-speed highway in Germany.
Here, "Autobahn" is contextualized as a place experiencing an event, specifically heavy traffic.
Auf der Autobahn war heute viel Verkehr.
There was a lot of traffic on the highway today.
Here, "Autobahn" refers to the physical roadway or highway.
Ich fahre jeden Tag über die Autobahn.
I drive over the highway every day.
In this sentence, "Autobahn" is used to refer to the general concept of highways in Germany and their characteristics.