This is the 391st most frequent Norwegian word.
rosenborg
"Rosenborg" is a proper noun in Norwegian, often referring to a district in Trondheim, a famous Norwegian football club (Rosenborg BK), or occasionally the Rosenborg Castle in Denmark.
Here, 'Rosenborg' refers to the name of a Norwegian football team.
Rosenborg vant kampen i går kveld.
Rosenborg won the match last night.
In this case, 'Rosenborg' refers to a historical castle located in Copenhagen.
Jeg besøkte Rosenborg slott da jeg var i Danmark.
I visited Rosenborg Castle when I was in Denmark.
Here, 'Rosenborg' is used as the name of a residential area.