Trenchcoat

Trenchcoats were coats made for protection from weather, famously worn on wars.

Worn by the Doctor
The Fourth Doctor wore a single-breasted trenchcoat of plum purple velvet when he and Romana II foil Tryst's conversion of Mandrels into Vraxoin. (TV: Nightmare of Eden) He also wore a burgundy trenchcoat, (TV: The Leisure Hive) up to his death. (TV: Logopolis)

The Seventh Doctor wore a black leather trenchcoat on Nazi Germany. (PROSE: Timewyrm: Exodus)

The War Doctor wore double-breasted leather trenchcoats on black (COMIC: The Whole Thing's Bananas) or brown. (COMIC: The Clockwise War, The Lost Dimension, Four Doctors; TV: The Name of the Doctor, The Day of the Doctor)

In World War I, the Ninth Doctor wore a British Army trenchcoat. (COMIC: The Forgotten)

The Thirteenth Doctor wore a lilac-blue trenchcoat with a midnight blue lining. (TV: The Woman Who Fell to Earth-The Power of the Doctor)

The Fourteenth Doctor wore a navy blue trenchcoat after regenerating. (TV: The Power of the Doctor)

Worn by companions
Sarah Jane Smith occasionally wore trenchcoats. (TV: Eye of the Gorgon, The Last Sontaran, The Mark of the Berserker, et al.)

Amy Pond wore a dark teal trenchcoat during her encounter with Vincent van Gogh. (TV: Vincent and the Doctor)

Donna Noble wore a single-breasted trenchcoat of tan leather. (TV: Turn Left, The Stolen Earth/Journey's End)

Susan Foreman wore a beige trenchcoat during her adventure on the Death Zone. (TV: The Five Doctors)

Tegan Jovanka wore a gunmetal trenchcoat with a steel blue trim during the Master's Dalek Plan. (TV: The Power of the Doctor)

Worn by the Master
The Master wore trenchcoats in some incarnations.

The Bruce Master wore a black leather trenchcoat. (AUDIO: Faustian-Passion)

The Spy Master wore a double-breasted trenchcoat of black leather when posing as a Nazi in Paris. (TV: Spyfall)

Worn by others
Detective Duggan wore a beige trenchcoat when he helped the Fourth Doctor and Romana II. (TV: City of Death)

Sally Sparrow wore a dark brown trenchcoat. (TV: Blink)

Vienna Salvatori wore leather trenchcoats done in navy, (AUDIO: The Shadow Heart-Vengeance) or black. (AUDIO: The Nemesis Express-Passion)

The Second Rani wore a black trenchcoat when posing as Professor Baxton. (AUDIO: The Rani Elite, Planet of the Rani)

One version of the Corsair with a bowler hat wore a black trenchcoat. (PROSE: Eleven Things You Probably Didn't Know About the Corsair)