This is the 3883rd most frequent German word.
straßenbahn
"Straßenbahn" means "tram" or "streetcar" in English.
Here, 'Straßenbahn' is used as a noun referring to a mode of transportation, specifically a tram.
Die Straßenbahn fährt direkt ins Stadtzentrum.
The tram goes directly to the city center.
In this sentence, 'Straßenbahn' is again used as a noun to denote the vehicle expected by the speaker.
Wir warten an der Haltestelle auf die Straßenbahn.
We are waiting at the stop for the tram.
Here, 'Straßenbahn' refers to the broader concept of a tram system or its individual lines.