This is the 2445th most frequent German word.
rolf
The word "rolf" does not have a meaning in standard German; it might be a name or slang.
Here, 'Rolf' is used as a proper noun referring to a person's name.
Ich habe gestern mit Rolf gesprochen.
I spoke with Rolf yesterday.
In this context, 'Rolf' is again a proper noun used to denote someone's name, along with possessive attribution.
Der Rolf meiner Kollegin hat gestern ein Buch veröffentlicht.
My colleague's Rolf published a book yesterday.
Here, 'Rolf' is referred to as a term whose meaning or representation is questioned, possibly as a colloquial or symbolic word.