(covers information from several alternate timelines)
A temporal inversion is a phenomenon which can be associated with instances of time travel.
29th century timeships initiated temporal inversions as part of the process of generating a temporal rift. Such a procedure was carried out by Henry Starling in 1996, when preparing to take the Federation timeship Aeon to the future. Upon initiation of the inversion, the Aeon's temporal field generator powered up, after which a rift could be formed. (VOY: "Future's End, Part II")
In 2390, Harry Kim and Chakotay used a stolen Borg temporal transmitter to send a message back in time to the year 2375, in order to save the starship Voyager, which had been destroyed in the Takara sector while attempting to utilize quantum slipstream drive to return to the Alpha Quadrant. By sending a new set of phase corrections to Seven of Nine's interplexing beacon, they were able to successfully change history by causing the slipstream to collapse, returning Voyager to normal space before the crash. This alteration to history constituted a temporal inversion, the effects of which Captain Braxton, a Starfleet officer from the 29th century, had to repair. (VOY: "Timeless", "Relativity")