Breast

Breasts, or boobs, (AUDIO: The Veiled Leopard, PROSE: Iris Wildthyme and the Polythene Terror) or more offensively known as t*ts, (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)

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)

Behind the scenes
The parodic Comic Relief story The Curse of Fatal Death had its version of the Master outfitted with "Dalek bumps", identified as etheric beam locators, which are placed in such a way that they appear to give the Master "breasts".

When the Ninth Doctor makes note of his "breasts", the Master insists that they're bumps, though he suggestively tells Emma that they are "extremely firm". After regenerating, the Tenth Doctor calls the Master "camp" and mockingly compliments him on his "nice tits", while the Eleventh Doctor believes the Master to be a girl. Finally, after regenerating into female form, the Thirteenth Doctor believes she has etheric beam locators, even pointing out an "on switch", leading Emma to inform her that they are actual breasts.