This is the 8167th most frequent Polish word.
ojcowa
"Father's" or "paternal" (possessive form in Polish).
Here, 'ojcowa' is used in a possessive sense, relating to something belonging to or associated with 'father'.
To jest dom mojego ojcowa.
This is my father's house.
'Ojcowa' is describing the father of the friend's family in this context.
Spotkałem ojcowa koleżanki.
I met my friend's father.
Here, 'ojcowa' is possessive, referring to the context of the father's childhood.