Burnt orange was a dark shade of orange.
The Fifteenth Doctor often wore a double-breasted trenchcoat of burnt orange leather with his striped cardigans. (PROSE: "Heroes of Time" [+]; TV: The Church on Ruby Road)
The Third Doctor wore a burnt orange cape when he and Jo Grant met Wetland Drashigs released from a miniscope by Kalik. (TV: Carnival of Monsters)
Yasmin Khan wore a burnt orange shirt under a black leather jacket when the Flux began. (TV: The Halloween Apocalypse, War of the Sontarans, Once, Upon Time)
Ace's black bomber jacket had a burnt orange lining. (TV: Silver Nemesis, The Greatest Show in the Galaxy, Survival)
Clara Oswald wore a burnt orange shirt with eye pictures when she and the Twelfth Doctor met Rusty during the Good Dalek incident. (TV: Into the Dalek)
Bill Potts wore a rainbow bodysuit done in ebony black, crimson, sapphire blue, white, burnt orange, and mustard yellow. (TV: The Pilot, Smile, Thin Ice, Extremis)
One of Missy's suits was burnt orange. (TV: The Caretaker)
At night, the sky of Susan Foreman's home planet was a burnt orange; (TV: The Sensorites, PROSE: The Sensorites) Gallifrey was described almost in exactly the same way by the Tenth Doctor many years later. (TV: Gridlock)
Martez, a mad scientist from Red Rocket Rising, wore a burnt orange shirt when possessing the body of Asha Gryvern. (AUDIO: Blood of the Daleks)