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)

When possessed by Cassandra, Rose Tyler unbuttoned her purple and blue patchwork blouse to partially show her breasts. When free, she remained showing them without shame. (TV: New Earth)

When possessed by gas, Carys Fletcher opened Gwen Cooper's black blouse and sees her breasts, realising it requires to feed on men. Gwen was unfazed by the moment, more concerned for Carys's welfare than her own. (TV: Day One)

Some of Martha Jones's tops partially show her breasts. (TV: Smith and Jones, The Shakespeare Code, Gridlock, The Sound of Drums, etc)

Women on the Georgian times wore dresses with their breasts partially shown including Reinette (TV: The Girl in the Fireplace) and Mary Shelley. (TV: The Haunting of Villa Diodati)

Peri Brown wore many tops partially showing her breasts. (TV: Planet of Fire, The Caves of Androzeni, Attack of the Cybermen, The Two Doctors, etc)

Grace Holloway wore a jade green opera dress with her breasts partially shown. (TV: Doctor Who)

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)

The Master and his Dalek bumps. (TV: The Curse of Fatal Death)

One incarnation of the Master worn "Dalek bumps", identified as etheric beam locators, which were placed in such a way that they appear to give the Master "breasts".

When the Ninth Doctor makes note of his "breasts", the Master insisted that they were 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", while the Eleventh Doctor believed the Master to be a girl. Finally, after regenerating into female form, the Thirteenth Doctor believed she 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)