Waistcoat

A waistcoat was an article of clothing.

Worn by the Doctor
Many incarnations of the Doctor wore waistcoats.

The First Doctor wore a beige tweed waistcoat with a fob watch. (TV: An Unearthly Child, The Daleks, etc.)

The Second Doctor sometimes wore waistcoats. (PROSE: Daleks Invade Zaos, Golem)

The Third Doctor wore a grey waistcoat with symbols when he first went to Peladon. (TV: The Curse of Peladon)

The Fourth Doctor wore waistcoats with cheques and fob watches. (TV: Terror of the Zygons, onwards)

The Sixth Doctor wore waistcoats on many styles. He first wore a knitted waistcoat that was dark brown, orange and purple in colour and featured dark green buttons, along with a dark green metal watch chain, (TV: The Twin Dilemma), a dark purple squared waistcoat, (PROSE: Burning Heart) a waistcoat with tweed pattern on the right side and a zig-zag pattern on the left, (PROSE: Time Wake) a plain brown waistcoat, (COMIC: Virtually Indestructible) a plain violet waistcoat, (COMIC: Endgame) and another with a blue striped theme. (AUDIO: Year of the Pig). He occasionally wore a navy blue one, (WC: Real Time) and also wore a brown and crimson tweed waistcoat with his 'Bletchley Tweeds'. (AUDIO: Criss-Cross, Quicksilver) His most prominent waistcoat became a red and white gingham waistcoat with bear face buttons, (TV: The Mysterious Planet) which he wore up to his death. (TV: Time and the Rani)

Right up to his death, the Seventh Doctor wore a scarlet brocade waistcoat. (TV: Doctor Who)

The Eighth Doctor wore some double breasted waistcoats of paisley-brocade with a gold fobwatch. (TV: Doctor Who) Soon, he wore single breasted waistcoats of mustard yellow velvet (COMIC: The Pictures of Josephine Day) or bronze paisley-brocade. (TV: The Night of the Doctor)

The War Doctor wore double-breasted moleskin waistcoats with fob watches under his leather trench coats either ginger, (COMIC: The Clockwise War) mahogany (COMIC: The Whole Thing's Bananas), mustard yellow, (COMIC: First Rule-Fast Asleep), or dark green-brown (TV: The Name of the Doctor, The Day of the Doctor) with 10 brass buttons and a fob chain attached to it.

When posing as John Smith, the Tenth Doctor wore a charcoal tweed waistcoat. (TV: Human Nature|The Family of Blood)

During his retirement to the Victorian era, the Eleventh Doctor wore a single-breasted waistcoat of plum purple velvet with a pocket watch. (TV: The Great Detective, The Snowmen) He also wore a grey moleskin waistcoat,, (TV: The Rings of Akhaten) a 6-buttoned black velvet waistcoat with lapels, (TV: Nightmare in Silver) before switching it with a light check pattern black waistcoat with smaller lapels. (TV: The Day of the Doctor) While in Victorian Yorkshire, the Doctor wore a brown chequered version of his burgundy attire. (TV: The Crimson Horror) He wore the plum purple velvet one on Trenzalore, and switched for the black oen with the light cheque before his death. (TV: The Time of the Doctor)

The Twelfth Doctor sometimes wore waistcoats. (TV: Mummy on the Orient Express, Thin Ice)

The Thirteenth Doctor wore a blue waistcoat with clock symbols during her first encounter with Ashad. (TV: The Haunting of Villa Diodati)

Worn by companions
Sarah Jane Smith sometimes wore waistcoats. (TV: The Last Sontaran, onwards)

Romana II wore a gold waistcoat when she and the Fourth Doctor met Nimons. (TV: The Horns of Nimon)

Ryan Sinclair and Graham O'Brien sometimes wore waistcoats. (TV: Nikola Tesla's Night of Terror, The Haunting of Villa Diodati)

Yasmin Khan wore a beige waistcoat with her ivory shirt and her bottle green walking suit. (TV: Survivors of the Flux, The Vanquishers)

While acting as his successor, Jack Harkness wore the Sixth Doctor's coat, including his seventh favourite waistcoat and yellow-stripped trousers. (AUDIO: Piece of Mind)

Worn by the Master
Many versions of the Master wore waistcoats.

The Tremas Master wore a silver waistcoat when he met the Seventh Doctor, Ace, and the Cheetah People. (TV: Survival)

As John Smith, the Decayed Master wore a charcoal waistcoat. (AUDIO: Master)

The War Master wore many waistcoats done in green-and-brown stripes cotton, (AUDIO: The Master of Callous) gunmetal grey tweed (AUDIO: Rage of the Time Lords), dark beige tweed. (AUDIO: Day of the Master), mustard yellow moleskin, (AUDIO: Killing Time), or wine brocade. (TV: Utopia)

The Spy Master wore a plaid moleskin waistcoat and trousers with a pattern of three vertical stripes interlocking with three lines of horizontal dashes, in varying shades of orange over a navy background.

Worn by others
Jenny Flint wore single breasted waistcoats done in blue (TV: A Good Man Goes to War) or grey. (COMIC: The Lost Dimension)

Emily Morris wore a cream waistcoat with tan stripes. (TV: Lost in Time)

Henry Jago and George Litefoot wore double breasted waistcoats. (TV: The Talons of Weng-Chiang)

When he thought he was the Doctor, Jackson Lake wore a double-breasted waistcoat of scarlet brocade under his tweed overcoat. (TV: The Next Doctor)

The Dream Lord wore a beige waistcoat with his tweed suit when he taunts the Eleventh Doctor, Amy Pond, and Rory Williams during the beginning of the Eknodine assault. (TV: Amy's Choice)

The Ringmaster of the Psychic Circus wore a double-breasted waistcoat of rainbow fabric. (TV: The Greatest Show in the Galaxy)

The Pied Piper wore a black waistcoat when posing as Mr. Spellman, director of Spellman's Magical Museum of the Circus. (TV: The Day of the Clown)

Verity Newman wore a charcoal waistcoat with her lavender blouse when she met the Tenth Doctor. (TV: The End of Time)