A spatial rift is a connection between two locations in space-time. A temporal rift is a type of spatial rift that also connects two points in time. (VOY: "Future's End") A spatial flexure is a type of spatial rift that allows spacecraft to travel vast distances. (VOY: "Q2")
After being transported to the Delta Quadrant in 2371, Captain Kathryn Janeway of the USS Voyager informed her crew that they will be on alert for wormholes, spatial rifts, or technologies that might aid their trip home. (VOY: "Caretaker")
When Voyager was duplicated by a divergence field in 2372, a spatial rift was formed on deck 15 connecting the two ships, which occupied the same physical space. (VOY: "Deadlock")
In 2377, Voyager encountered a spatial rift that emitted high levels of neutrinos and chronitons. It produced a chronokinetic surge that struck the ship, interacting with its warp core and splitting it into different time frames. (VOY: "Shattered")