wormholes are time machines. recall the classic wormhole demonstration we've all seen:
a pencil is pushed through a folded piece of paper. the paper represents the 2nd dimension, and the pencil is a shortcut.
of course, the pencil must take advantage of the 3rd dimension to make this jump.

which of course means a wormhole connecting points in the 3rd dimension is a 4th dimensional entity.
the 4th dimension is time. so what would a 5th dimensional wormhole do? transport you through the 4th dimension, time. time is a location.