This is the 790th most frequent Bulgarian word.
атанас
"Aтанас" is a Bulgarian male given name, equivalent to "Atanas" in English.
In this sentence, "Атанас" is used as a proper noun, specifically someone's first name.
Атанас е мой приятел.
Atanas is my friend.
Here, "Атанас" represents possession, as the book belongs to Atanas, using the possessive form.
Книгата на Атанас е на масата.
Atanas's book is on the table.
In this context, "Атанас" is the recipient of an action within the sentence.