in the world

[in the world] or [on earth] {adv. phr.}, {informal} Of allpossible things; ever. - Usually used for emphasis after words thatask questions, as "who", "why", "what", etc.

Where in the world didyou find that necktie?

The boys wondered how on earth the mousegot out of the cage.

Betty could not understand what on earth theteacher meant.