This is the 404th most frequent Hebrew word.
משפחת
The Hebrew word "משפחת" means "family of."
In this sentence, "משפחת" refers to a specific family (the Cohen family) and indicates possession of something related to the family.
משפחת כהן חוגגת היום יום הולדת.
The Cohen family is celebrating a birthday today.
Here, "משפחת" establishes association to a family (the Levi family) and introduces a specific relation to the mentioned entity.
ראיתי היום את הבת של משפחת לוי.
I saw the daughter of the Levi family today.
In this sentence, "משפחת" is used figuratively to reference humanity as a familial unit.