Time stream

The time stream was the pathway for the movement of time.

Universal time streams
The inhabitants of an unnamed planet were in a different time stream from the rest of the universe. When the First Doctor and Ian Chesterton visited the planet, a few minutes passed for them, but the inhabitants lived through their entire civilisation from their rise and fall. (AUDIO: Rise and Fall)

The Graxnix were removed from the time stream by the Tenth Doctor, trapping them between seconds. (COMIC: Hotel Historia)

The Two Streams Facility of Apalapucia used time streams (which was the source of the name). Apalapucians with the Chen-7 plague were kept in the facility in different time streams, allowing them to live out their whole lives in 1 day. This also meant that each patient was kept isolated in a different time stream, but in the same place. (TV: The Girl Who Waited)

Individual time streams
Professor Chronotis' TARDIS could interfere with an individual's time stream. (HOMEVID: Shada, WC: Shada, AUDIO: Shada)

The Doctor's time stream
While awaiting his death at Lake Silencio, the Eleventh Doctor had the Teselecta send letters to Amy Pond and Rory Williams, River Song, Canton Everett Delaware III, and a younger version of himself. He explained that to deliver the messages himself, it would involve crossing his own time steam, "best not", he remarked. (TV: The Wedding of River Song)

The Doctor's time stream appeared as an open wound in the fabric of reality inside the ruins of the Doctor's TARDIS in the future on Trenzalore, where the Doctor was buried. The Great Intelligence, in the form of Walter Simeon, arrived on Trenzalore, accompanied by faceless humanoids called the Whisper Men, who he used to bring several of the Eleventh Doctor's friends there to draw him out so he could invade his time stream, turning all of his victories into defeats and having his ultimate revenge. He did so by directly entering his time stream inside the ruined future TARDIS. However, this plan was foiled by Clara Oswin Oswald, who followed the Great Intelligence through the wound. Just as he was, she was ripped into countless versions of herself throughout history and saved various incarnations of the Doctor countless times. (TV: The Name of the Doctor)