Great House

A Great House was a bloodline or Family of Time Lords. Each House used its own Looms to create new members. The collective term "Great Houses" was often used as a word for Time Lord society and culture, or specifically for the Great Houses who participated in the War in Heaven.

Description
The Great Houses were more like "wave[s] of some fundamental universal force" than family trees. (PROSE: Weapons Grade Snake Oil) Members were laterally rather than directly related, so they addressed each other as cousins. Each House was allowed to have a specific number of members. (PROSE: Lungbarrow)

Time Lords of Newblood Houses were loomed with a second heart (PROSE: Christmas on a Rational Planet) and had better rebirth-control than older Houses; (PROSE: Christmas on a Rational Planet, The Book of the War) for this reason, they viewed regeneration as trivial and never played Eighth Man Bound at the Academy. (PROSE: Christmas on a Rational Planet) Newblood Houses were more likely to produce interventionists, and some even viewed time-active cultures as not being lesser species; for these reasons, they were often regarded by Oldbloods as smug and ambitious upstarts. Despite its long lineage, House Dvora came to be seen as one of the first Newblood Houses after it produced the Imperator; however, it was far more stable than the eccentric Newbloods that would spring up during the War in Heaven. (PROSE: The Book of the War)

Each Great House had House-Foundations within the Homeworld's wider reproductive matrix, as well as a Chapterhouse with which it shared an essential tie; if the Chapterhouse fell into neglect, the House itself would unravel. Chatelaines from other Houses were often assigned to maintain chapterhouses whose Great Houses had fallen into obscurity. (PROSE: The Book of the War)

Time Lords' full names often included the name of their Great House. The full names of Quences, Andred, (PROSE: Lungbarrow) Ruthven, (PROSE: The Book of the War) Romana, (TV: The Ribos Operation, AUDIO: Panacea) Ruath, (PROSE: Goth Opera) Thoth, (AUDIO: Body Politic) and Goralschai, as well as all the members of House Meddhoran, included the name of their Great House. (PROSE: Against Nature) If a Great House was ashamed of one of its members, they could undergo Elective Semantectomy to remove that member's name from history. (PROSE: Weapons Grade Snake Oil)

Maris described the Great Houses of Gallifrey as "highborns". (PROSE: Celestial Intervention - A Gallifreyan Noir) Ashildr considered the Doctor to be a "highborn Gallifreyan". (TV: Hell Bent)

History
Some Great Houses were even older than Rassilon. (PROSE: Cat's Cradle: Time's Crucible) Their chapterhouses were the oldest living things on Gallifrey. (PROSE: Lungbarrow)

During the Time Lords' war against the Great Vampires, many Great Houses were infected with and corrupted by the vampiric taint. (PROSE: Blood Harvest)

Some Great Houses were named after their founders or most illustrious members. There existed Great Houses named after General Mirraflex, (PROSE: The Book of the War) Rassilon, (AUDIO: Desperate Measures) Fordfarding, (PROSE: Cat's Cradle: Time's Crucible, The Infinity Doctors) Lolita, (PROSE: The Book of the War) and Prydonius. (PROSE: Cat's Cradle: Time's Crucible)

A group of ruling Houses called Chapters played major roles in politics surrounding the Presidency. (TV: The Deadly Assassin, PROSE: The Book of the War) Most Great Houses were affiliated with one of these Chapters. (PROSE: Lungbarrow) During the War in Heaven, many of the ruling bloodlines developed Newblood sub-lines dedicated to exploring particular genetic philosophies, usually including experiments with biodiversity or the lesser species. (PROSE: The Book of the War, Against Nature)

Ruling Houses
Two of the original ruling Houses during the anchoring of the thread were called "House Ixion" and "House Catherion" by The Book of the War. After a long, slow decline, they were eventually replaced by Houses Mirraflex and Lineacrux. (PROSE: The Book of the War)

The six Chapters during the Doctor's life were the Prydonian Chapter, the Arcalian Chapter, (TV: The Deadly Assassin) Patrex House, (TV: The Deadly Assassin, AUDIO: Neverland) the Dromeian Chapter, the Cerulean Chapter, (PROSE: Lungbarrow) and the Scendeles Chapter. (PROSE: The Ancestor Cell)

During the War in Heaven, the ruling Houses were almost continually replaced. By the fiftieth year, the six ruling Houses were Dvora, Tracolix, Lineacrux, Arpexia, Xianthellipse, and Mirraflex. (PROSE: The Book of the War)

Other Houses

 * House Bluewood (PROSE: A Farewell to R.M.S.)
 * House of Blyledge (PROSE: Cat's Cradle: Time's Crucible, Cold Fusion)
 * House of Brightshore (PROSE: Divided Loyalties)
 * House of Deeptree (AUDIO: Lies)
 * House of Everston (AUDIO: Panacea)
 * House of Fordfarding (PROSE: Cat's Cradle: Time's Crucible, The Infinity Doctors)
 * House of Heartshaven (AUDIO: Panacea)
 * House of Jade Dreamers (AUDIO: Zagreus)
 * House of Jurisprudence (AUDIO: Insurgency)
 * House Lolita (PROSE: The Book of the War)
 * House (of) Lungbarrow (PROSE: Lungbarrow, Crimes Against History)
 * House Meddhoran (PROSE: Against Nature)
 * House of Oakdown (PROSE: Divided Loyalties)
 * House Paradox (PROSE: Alien Bodies)
 * House of Rassilon (AUDIO: Desperate Measures)
 * House of Redlooms (PROSE: Lungbarrow, The Taking of Planet 5)
 * House of Stillhaven (PROSE: Divided Loyalties, Lords and Masters)
 * House Urquineath (PROSE: Weapons Grade Snake Oil)
 * House of Wetrix (AUDIO: The Conscript)

Spurious Houses
The Eremites were sometimes referred to as a Great House by their apologists on the Homeworld.

During the War in Heaven, some Cwejen petitioned for greater rights and recognition as a bloodline, which earned them the satirical name "Little House of Cwejes". Cousin Gable used similar Army of One technology to create six copies of himself, which he called the House of the Seven Gables.

During the War, Remote weaponstores grew to such size that, if united, they could have made a claim to being a Great House. (PROSE: The Book of the War)

Behind the scenes

 * Several Great Houses which originate from Faction Paradox have been directly acknowledged in BBC-licensed content: House Dvora in AUDIO: Panacea, House Mirraflex in AUDIO: The Conscript, and House Lineacrux, House Arpexia, House Urquineath, and House Meddhoran in a Facebook quiz posted on the official Doctor Who Facebook page on 23 March 2019.