This is the 68th most frequent Swedish word.
hans
"His" (possessive pronoun).
The word 'hans' is used as a possessive pronoun indicating that the book belongs to the subject referred to as 'him'.
Hans bok är på bordet.
His book is on the table.
Here, 'hans' again acts as a possessive pronoun pointing to the ownership of the car by the subject described as 'him'.
Jag såg hans bil på parkeringen.
I saw his car in the parking lot.
The possessive pronoun 'hans' conveys that the words belong to the male subject being spoken about.