Dive for the ball

[Kontol]

I can't find the word "dive for" in the dictionary. Is it a verb followed by the preposition "for?" If yes, what does "for" mean here?

The goalkeeper dived for the ball.

 

[emsr2d2]

We've asked this before and we're going to keep asking it. Are you WATCHING football matches? If you're a football fan, you'll have seen plenty of examples of a goalkeeper diving for the ball. Forget the dictionary. Do you really not understand what movement the goalie is making that results in this sentence?