Breast

Breasts, or boobs, (AUDIO: The Veiled Leopard, PROSE: Iris Wildthyme and the Polythene Terror) bosoms, (TV: The Curse of Fatal Death) doo-dahs, (AUDIO: The Resurrection of Mars) or more offensively known as tits, (TV: Combat) were organs commonly found on human females. Circular in shape, nipples were located on the centre front of breasts. (PROSE: Cat's Cradle: Warhead) Unfortunately, it was possible for breasts to have cancer, which could be fatal. (AUDIO: Hostile Environment)

Breast implants were composed of plastic. (TV: Rose)

Serena had "enormous, unforgiving breasts" which she covered with a cardigan. (PROSE: I Am a Dalek)

Irving Braxiatel owned champagne glasses moulded on Marie Antoinette's breasts. (PROSE: The Doomsday Manuscript)

Lucie Miller had to strap down her breasts, (AUDIO: The Resurrection of Mars) while masquerading as Brother Lucianus. (AUDIO: The Book of Kells)

Jeremy Fitzoliver made note of the "boobs" on a tourist talking to Max Vilmio. (AUDIO: The Ghosts of N-Space)

While wearing a telepathy pendant, Toshiko Sato heard a woman thinking of when she was sat with her "boobs like something out of the National Geographic." (TV: Greeks Bearing Gifts)

Tommy claimed that his girlfriend was never happier than when she was "flashing [her] tits at a passing dickhead." (TV: Combat)

One incarnation of the Master gained "Dalek bumps", identified as etheric beam locators, which were placed in such a way that they appeared to give him "breasts". When the Ninth Doctor pointed this out, the Master insisted that they were only bumps, though he suggestively told Emma that they were "extremely firm". After regenerating, the Tenth Doctor called the Master "camp" and mockingly complimented him on his "nice tits", whereas the Eleventh Doctor felt shy because he mistook the Master to be a girl. Finally, after regenerating into female form, the Thirteenth Doctor believed she herself had etheric beam locators, even pointing out an "on switch", leading Emma to inform her that they were actual breasts. (TV: The Curse of Fatal Death)

Horror had large breasts with nipple piercings, which her friend Inangela Marrero could see through her t-shirt when it rained. When Horror and Valentine Bregman were being transported into the Ship of War, she stepped towards him and he felt her "fat tit" rub against the side of his arm. When Inangela encountered a thinner Horror from the future, she noticed that her breasts were no longer "what they were". (PROSE: This Town Will Never Let Us Go)

Behind the scenes
In a corporate video filmed by Jon Pertwee circa 1981, the Third Doctor accosted a British couple in an appliance shop, telling them that he had just returned from the planet Zanussi, and explained the value of the Zanussi appliance manufacturer's five-year warranty. When the wife asked "Just where in the galaxy is Zanussi?", the Doctor glanced at her body and replied, "Show us your tits and I'll tell you."