John 17:24

Greek πρὸ καταβολῆς κόσμου. "before/in front of foundation world." For as much as "the World" was definitive previously with a definite article being used in every case, why all of a sudden the lack of definite articles here?

In the genitive, without specific bias forced into it, and words added, we simply read, "before a foundation of a world."