3D

"3D", occasionally spelled "3-D", was an undefined trait that Martha Jones, in 6012, attributed to a three-dimensional map on Messaline. (TV: The Doctor's Daughter)

By the early 21st century, televisions were capable of 3D broadcasting. (PROSE: Cat's Cradle: Warhead) By the 27th century, some "vidgames" were in 3D; a hostess once offered the Tenth Doctor a "modem link for 3D vidgames." (TV: Midnight) By 4123, tickets were in 3D as well; Solana Mercurio once gave visitors to the Ood Sphere what she referred to as "3D tickets." (TV: Planet of the Ood)

The Tenth Doctor used a pair of 3D glasses when observing the effects the Void had on people and objects. (TV: Doomsday)

Behind the scenes
A trailer for the fifth series of Doctor Who was released in 3D, in cinemas and on YouTube, on 20 February 2010.