This is the 3564th most frequent Polish word.
borysa
"Borysa" is the genitive or accusative form of "Borys," a Polish masculine name equivalent to "Boris" in English.
The word "Borysa" is used here in its instrumental form to indicate the person Borys as the companion while walking.
Spacerowałem po parku z Borysem.
I was walking in the park with Borys.
The word "Borysa" appears in its accusative form, showing that Borys is the direct object of the verb "see."
Czy widziałeś Borysa wczoraj?
Did you see Borys yesterday?
The word "Borysa" is presented in the genitive case to express possession or attribution of characteristics related to Borys.