A time warp was a kind of time distortion, (PROSE: Forever Autumn) which felt like being "tumble-dried." It left a temporal residue that could be detected. (AUDIO: We Are The Daleks)
Time warps could be caused by gravitic warping of normal time-progression, resulting in lateral stasis like a time loop. The Flying Dutchman II had been trapped in one for 628 years before Kroton the Cyberman helped to break it, inadvertently resulting in the passengers rapidly aging to death. (COMIC: Ship of Fools)
Movellan ships possessed time warp capabilities, (TV: Destiny of the Daleks) being able to make time jumps over thousands of years. (AUDIO: The Movellan Grave)
A time contour was a form of time warp, also referred to as a "time slip." (TV: Time-Flight)