This is the 17712th most frequent Polish word.
znajomy
An acquaintance.
Here, 'znajomy' is used to mean a 'friend' or 'acquaintance' that the speaker has a connection with.
Znajomy powiedział mi o tej książce.
An acquaintance told me about this book.
In this case, 'znajomy' refers to a broader group of people the speaker knows but might not be very close to.
Mam wielu znajomych w tym mieście.
I have many acquaintances in this city.
Here, 'znajomy' is used to describe someone the speaker knew in the past who they have reencountered.