1) Apple bug 2) Astronomical hypothesis 3) Exotic matter 4) Garden creature product 5) Hole 6) Hole made by a burrowing worm 7) Hollow 8) Theoretical space passageway 9) Unwelcome sight on an apple 
A wormhole, also known as an Einstein–Rosen bridge, is a hypothetical topological feature of spacetime that would fundamentally be a `shortcut` through spacetime. A wormhole is much like a tunnel with two ends each in separate points in spacetime. For a simplified notion of a wormhole, visualize space as a two-dimensional (2D) surface. In this.....[video game] Wormhole is an abandonware game. It was developed and published by Centerfleet games, but promptly abandoned in 2002 after a series of events that left Centerfleet with the name Centerscore. Gameplay consisted of fast-paced space shooting, remarkably similar to asteroids. Each player spawned in his/her own area, and the goal of...
• (n.) A burrow made by a worm.
A hypothetical 'tunnel' connecting two different points in spacetime in such a way that a trip through the wormhole could take much less time than a journey between the same starting and ending points in normal space. The ends of a wormhole could, in theory, be intra-universe (i.e. both exist in the...
Worm'hole` noun A burrow made by a worm. 
[n] - hole made by a burrowing worm
noun hole made by a burrowing worm