Gender

Gender was a construct, (AUDIO: The Boundless Sea) and a sense of identity, relating to whether one was male, female, masculine, feminine, or anywhere along a diverse spectrum of gender identities. (PROSE: Island of Death) It was a matter of self-designation. (AUDIO: The Sword of the Chevalier) Gender was a fluid concept, varying from person to person, culture to culture, and species to species. (COMIC: Ophiuchus)

As the Fifth Doctor explained: "Gender is a very fluid concept, Nyssa. For some people, more than others. A Time Lord even more so."

- Fifth Doctor, explaining gender

Amy Pond had met species with only one gender, or three, or, in one case, seventy-two. (PROSE: Borrowed Time) One species switched gender every two minutes. (AUDIO: Summer of Love) Among some species, like the Makemono, there was no such thing as gender, (PROSE: Chicken Fried Banana Republic) and many aliens were of indeterminate gender to Bernice Summerfield. (PROSE: Happy Endings) Robots in the Haven had no concept of gender, (AUDIO: The Cannibalists) nor did the Sontarans, a clone race. (TV: The Time Warrior, The Snowmen, et al.)

Torcaldians, who did not "specialise in one or the other", in terms of producing offspring, paid little mind to gender or its assignment. For instance, Freltese was mother of Ecsilo, and father of Jeyi. Ian Chesterton and Barbara Wright tried desperately to determine the genders of their kind, according to beards and signs of pregnancy, but found no luck, and the First Doctor urged them to "cast aside these preconceptions". (PROSE: The Ruins of Time)

Gender roles could be restrictive, (PROSE: Erasing Sherlock) and, along with sexual preference, might dictate one's fashion choices. (PROSE: This Town Will Never Let Us Go) In some time periods, gender severely limited one's clothing options. (TV: The Crusade) According to the Fifth Doctor, times when gender could dictate what one could or could not do were always "unsophisticated times". (PROSE: The Immortals)

Among humans, gender was not always a fixed trait. For instance, Cassandra O'Brien.Δ17 said she was once a "little boy" on Earth. (TV: The End of the World) While gender was commonly assigned at birth, (TV: Day of the Moon, Father's Day) trans people, such as Mickey Smith's friend Sally Salter, (PROSE: Rose) or Eleanor Blake, later realised they had always been a different gender, after all. (AUDIO: The Jabari Countdown) Indeed, as the Tenth Doctor affirmed, it was up to the individual to determine their own gender. (AUDIO: The Sword of the Chevalier)

Eleanor faced violence and discrimination on 20th century Earth on account of her gender, but as the centuries went on, trans people gained rights, and were able to live their lives more openly, without fear of condemnation. In the 30th century, home to Chris Cwej, people had no reason to care about such things. (AUDIO: The Jabari Countdown) Similarly, the Tenth Doctor understood that the Chevalier d'Eon could decide on her own gender, calling gender assignment an "archaic concept", and opting to respect the Chevalier's current pronouns. (AUDIO: The Sword of the Chevalier)

Physical characteristics could also affect how one was brought up. Charles "Chick" Peters was born with both an X and a Y chromosome like most men, but his body did not respond to the hormones like it normally would have. He was brought up as a girl by his parents, and came to realise his true identity at the age of fifteen. Chick did not have a womb. He dated women, and "never had any complaints" about his "female" body. Chick identified as a man, and did not consider himself a lesbian. (PROSE: Blue Box)

Illixtrians had more than one gender, and segregated their genders in the workforce. (PROSE: The Great Escapes)

Followers of the Unknown Ancestor revered individuals with ambivalent or multiple gender. As a result, Keth Marrane was accepted as completely androgynous, "male or female as the circumstances may warrant", and given complete access to their segregated society. (PROSE: A Hundred Words from a Civil War)

Time Lords and gender
The Tenth Doctor told Rose Tyler that the Time Lords considered concepts like gender to be archaic. (AUDIO: The Sword of the Chevalier) In fact, the Thirteenth Doctor said she was "not [a] man or woman in the way you understand it", (PROSE: The Good Doctor) and the Eighth Doctor firmly denied ever having been a man or a woman. (PROSE: Interference - Book One, Beltempest)

Nevertheless, Time Lords could be considered men, women, and "those of indeterminate gender". (PROSE: Happy Endings)

Prior to Rassilon, Gallifrey was ruled by matriarchal Gallifreyan leaders, the Pythia. (PROSE: Cat's Cradle: Time's Crucible) With regeneration in play, gender could change from one incarnation to another. (TV: The Doctor's Wife, Dark Water, Hell Bent, Twice Upon a Time, PROSE: Interference - Book Two) As a result, the Fifth Doctor explained, gender was quite fluid in their society. (COMIC: Ophiuchus) told River Song that getting a new gender in regeneration was "not really a big change". (AUDIO: The Bekdel Test)

The Twelfth Doctor explained to Bill Potts that the "most civilised civilisation in the universe" was billions of years beyond petty human obsession with gender and its associated stereotypes. However, she pointed out that they still called themselves Time Lords. (TV: World Enough and Time) Although "Time Lady" was also used, considered the term "old-fashioned". (TV: Dark Water)

Later, while pretending to be the Doctor, Missy referred to Nardole and Bill as "Exposition and Comic Relief". When Nardole retorted that they weren't functions, she responded "Darling, those were genders." (TV: World Enough and Time)

Gender among the Ulk-Ra
Because female Ulk-Ra were expected to be rationalists, as well as decision-makers and battle strategists, poetry was restricted to males who made it to old age.

As a coming-of-age ritual, young Ulk-Ra boys would be sent into the forest to kill a beast and return wearing its pelt. Those who succeeded were allowed to remain male, and grow into warriors, whereas those who failed had their genitals removed, and were forced to eat Issu-mul berries until they developed female characteristics, to become thinkers in their tribe. Youngsters of their species could also be induced to become males, out of necessity.

Males who survived this tradition were expected to be strong, territorial, and ambivalent toward pain. They were suited for war, and had their own gods. An Ulk-Ra tribe without males was vulnerable to other tribes. Ossu-male ate Issu-mul berries in order to "think hard", to find his tribe. Before becoming Ossu-female, hir was Ossu-hir, "not male or female, not suited for war or thought, or for land or sea". This is the state in which Ossu died, burning at sea. (PROSE: War Crimes)

History
Gender roles varied greatly across cultures and time periods.

Gender roles on Earth
In the Tribe of Gum, on Earth circa 100,000 BC, "strong leaders" were exclusively men, who held the power to make decisions, "not old men and women". Women were not listened to. Hur was seen as a prized possession, owed to the leader of the tribe, and as his mate, she was willing to give herself to him. (TV: An Unearthly Child) By contrast, Nefertiti, an Egyptian queen from 1334 BC, refused to be seen as a possession by Solomon, a 24th century pirate. (TV: Dinosaurs on a Spaceship) Earlier, Hatshepsut, Egyptian Pharaoh in the 18th Dynasty, (PROSE: Wardenclyffe) wore a false beard, and was addressed as King. (AUDIO: The Eye of Horus)

Antiquity
In Rome, women were said to have "weak minds". Many, like Marcia, wished that men would recognise their skills, imaginations and intelligence. Though women in many ways lacked autonomy in the Roman Empire, the wife of a wealthy merchant, for instance, might have a great deal of power within the household, at least over slaves. However, women in Rome could only exercise influence in the public sector by persuading their husbands to carry out their wishes. A lady's status, as well, simply reflected that of their husband. Some cults, temples and ceremonies across Rome were gender-specific, including the cult of the Bona Dea (PROSE: Sarah Jane and the Temple of Eyes) and the Sibylline Sisterhood, (TV: The Fires of Pompeii) which were exclusive to women. As contemporary historical records were all written by men, however, very little information on the lives of women away from menfolk survived into Sarah Jane Smith's time. (PROSE: Sarah Jane and the Temple of Eyes)

In the 1st century AD, Boudica was the Celtic queen of the Britons. She inherited half of Prasutagus' kingdom after his death. She fought many battles, and took no prisoners. Though Boudica was obeyed without question, Bragnar, a cook, was considered lesser for being a girl. In 60, Boudica marched with her army of thousands to Camulodunum and Londinium, slaughtering everyone to avenge her people following the actions of Rome. (AUDIO: The Wrath of the Iceni)

Middle Ages
By the 13th century, English culture dictated that women ought to be subservient to men. According to Irongron their purpose was "to do the lowly work". Sarah Jane Smith, travelling from the 20th century, questioned the notion that men "owned the world", and told Meg they were being worked like slaves, always cooking and carrying for the men. (TV: The Time Warrior) Meg believed this was simply their place in the world, stating:

Around 1190, it was not expected that "a lady" would venture out on her own. Women were also threatened when they spoke their mind on the actions of men. The First Doctor and Ian Chesterton tried to appeal to Richard I by telling him that their lost friend was a woman, demanding he take pity on her. (TV: The Crusade)

Around 1599 in England, women doctors were unheard of. Indeed, to William Shakespeare, even women actors and writers were the stuff of fantasy. Men played women's roles on stage. (TV: The Shakespeare Code)

17th century
According to the Thirteenth Doctor, the witch trials of the 17th century were targeted specifically at women, serving to execute those who got out of line, stood out, or made a stand. The Doctor agreed with Becka Savage that "These [were] hard times for women." In this era, it was inconceivable for a woman to hold any high office, such as Witchfinder General. King James I believed that women had an "innate aptitude for nosiness and gossip", and were often agents of Satan. The ducking stool was invented in order to silence "foolish women who talk[ed] too much". (TV: The Witchfinders) Educated women, such as healers, were frequent targets in 17th century witch hunts. (AUDIO: The Witch from the Well; TV: The Witchfinders) When the Doctor herself was accused of being a witch, she acknowledged that she would not have had to deal with this delay if, like past incarnations, she were "still a bloke."

Some of the King's motivation for encouraging these witch trials stemmed from his own feelings towards his mother, who had abandoned him. At the end of a shared adventure involving the Morax, the Thirteenth Doctor convinced King James to end the witch hunts. (TV: The Witchfinders) According to another account, the Twelfth Doctor helped end the witch trials. (COMIC: Witch Work)

18th century
In the 18th century, women were said to belong to the "weaker sex". They were not seen by men as fit for leadership positions. (AUDIO: The Avenues of Possibility)

Jeanne-Antoinette Poisson remarked that all women in France desired to be the King of France's mistress. When the King noted that Reinette wanted to see the Tenth Doctor again before her death, and spoke of him often, he said "you know how women are". (TV: The Girl in the Fireplace)

19th century
Elizabeth Garrett Anderson became the first woman doctor in England, by gaining entrance to the Worshipful Society of Apothecaries. In so doing, she paved the way for an Act of Parliament allowing all women to pursue this profession. (COMIC: Nurse Who?)

Early 20th century
At the time of the Mexican Civil War, Arturo Villar declared, "Women should never think." Of Zoe Heriot, he said, "For such a little woman your mouth is too big." Zoe, who hailed from the late 21st century, considered his ideas about women "knowing their place" quite primitive. (TV: The War Games)

Even children's toys were considered gendered in this era. Tom Braudy was taught that space LEGO was for boys only, while girls liked building hairdressers and flower shops. For this reason, he thought that girls could not be astronauts. (AUDIO: Memory Lane)

By the late 1900s and early 1910s, suffragettes fought hard for women's suffrage, rallying to gain the right to vote. (AUDIO: The Suffering, PROSE: Human Nature, Birthright) They were led by Emmeline Pankhurst, (PROSE: Birthright, Forgotten, Casualties of War) who held regular meetings, (PROSE: Forgotten) and had gained the attention of the British Prime Minister by 1909. (PROSE: Birthright) They were more active in London than on the English countryside. (TV: Human Nature)

Women had a greater role in British society during World War I, as the men were away at war. Around the end of the Great War, women finally gained the right to vote. (AUDIO: The Jabari Countdown) Some women, like Molly O'Sullivan, also took part in the war effort, taking care of the battle-scarred male soldiers. (AUDIO: The Great War)

Around this time, the notion arrived that a woman could "make her own way in the world", without a husband. (TV: The Unicorn and the Wasp)

Nevertheless, in 1924, many men thought women should not participate in academia; those women who did were thought to be "such bluestockings". (AUDIO: The Boundless Sea) 1926 saw no women in the police force, either. (TV: The Unicorn and the Wasp) Reginald Bassett would not speak of ghastly things around a "lady". (AUDIO: The Auntie Matter)

In the field of archaeology, it was considered inappropriate for a woman to enter a newly discovered historical site before any men. This was "no job for a girl". When Colonel Lifford had no choice but to ask Daphne Garsington to enter a Surene tomb first, to set up lighting, he made sure to clarify, "Of course, it's just the outer chamber. Leave the inner rooms to the chaps, huh? Don’t want you getting lost down there." Nevertheless, she was delighted at the opportunity, and declared that she was doing it "for women". (AUDIO: The Boundless Sea)

Women did not fight in the Royal Air Force during World War II, (AUDIO: The Renaissance Man) though some aided the British Army in the 1940s as code-breakers. (AUDIO: The Jabari Countdown, PROSE: Who Killed Kennedy, TV: Captain Jack Harkness) While Rachel Jensen found success in Alan Turing's Cambridge Group at Bletchley Park, (PROSE: Who Killed Kennedy) Eleanor Grainger could only find work at Bletchley as a "glorified typist". (PROSE: Ancient Whispers)

20th century Earth was particularly hostile to trans people, like Eleanor Blake. Eleanor chose to keep her birth-assigned gender a closely guarded secret. She was scared of others finding out. Despite others' non-acceptance, Eleanor was fully aware that she had "always been Eleanor". Arbuckle responded with violence when he found out, and also refused to refer to Eleanor by her name or pronouns, even opting for "young man" to rile her up.

However, Chris Cwej, hailing from the 30th century, had no such prejudice. He instilled a new confidence in Eleanor, through his own perspective of the universe. During their efforts against the Jabari, Chris and Eleanor developed a romantic bond, and he defended her against Arbuckle. When the adventure was over, having gained a clearer understanding of who she was, Eleanor asked the Seventh Doctor if people like her would be able to live freely and openly within her lifetime. (AUDIO: The Jabari Countdown) He responded:

Eleanor opted to travel in space with Alpha Wheeler, rather than return to her ordinary world, so that she might live truthfully without fear of consequence. (AUDIO: The Jabari Countdown)

Mid-20th century
In 1950s England, housework was considered exclusively a women's job, at least by Eddie Connolly. (TV: The Idiot's Lantern) By contrast, the use of weaponry was seen as only men's domain. (TV: Dinosaurs on a Spaceship)

In 1960s England, men were expected to do the heavy lifting, rather than "let the women do the job for [them]". (TV: "The Forest of Fear")

Women were often kept out of the action, in relative safety. Victoria Waterfield wanted to join the men, but the Second Doctor convinced her that she was far more valuable away from the danger. (TV: The Tomb of the Cybermen)

Helen Sinclair's father believed that only men were important in the world. Helen was determined to prove him wrong, especially as he mistreated her and her mother. (AUDIO: Absent Friends)

One professor in 1963 held that women were not suited to serious academic study, as "they tend[ed] towards emotionalism" and lacked the necessary "temperament". He promoted a far less skilled employee at the British Museum, Timothy, over Helen Sinclair. (AUDIO: The Red Lady)

According to Helen, there were not an abundance of opportunities in 1960s London for one who was "educated, ambitious and female". She joked that she often wished to be a 55-year-old man named Kenneth. (AUDIO: The Satanic Mill)

She felt that in this time period, privileged, powerful men were always bossing her around. In her travels across time and space, Helen was sometimes disappointed to find things were no different elsewhere. (AUDIO: World of Damnation) She left her world to travel with Liv and the Eighth Doctor because she felt the 20th century had no place for a woman like her, and in part to evade the authorities. (AUDIO: The Red Lady, The Satanic Mill)

Dr Kurdi spent her whole medical career being dismissed by her colleagues due to her gender and skin colour. (AUDIO: The Rise of the New Humans)

Women's liberation movement
By the 1970s, (TV: The Invasion) women's lib began taking traction on Earth. As Sarah Jane put it, this was the position, among women, that men had no right to push them around. (TV: The Monster of Peladon)

It was still remarkable when women were placed in positions of authority. (AUDIO: The Scream of Ghosts) Indeed, men were reluctant to select a woman for a research position, even when she was the obvious candidate. (AUDIO: Primord)

In 1975 (AUDIO: Last of the Cybermen) or around 1979, Isobel Watkins objected to Brigadier Lethbridge-Stewart's assertion that photographing Cybermen was "no job for a [woman]". Jamie McCrimmon agreed with the idea that men were inherently superior. Zoe Heriot and Isobel were outraged by both their "bigoted, anti-feminist remarks". (TV: The Invasion)

When she found out that the Brigadier gave instructions for her not to see a dead body in a hospital morgue, as such things were not fit for a young woman's eyes, Jo Grant called him a chauvinist and gained a new resolve to join the Third Doctor in his investigation. (AUDIO: The Rise of the New Humans)

Dr Ruth Ingram believed that both 's dictatorial manner and his courtesy came from "a bland assumption of male superiority". (TV: The Time Monster)

Peri Brown, from 1984, (AUDIO: The Reaping) called the Sixth Doctor a chauvinist for blaming his misadventures on the TARDIS herself. (AUDIO: The Song of Megaptera)

Valentina Tereshkova became the first woman to journey into outer space in the 1960s. (AUDIO: 1963: The Space Race, Thin Ice) Eileen Collins and Pamela Ann Melroy joined this list of female astronauts to have reached the stars by the end of the century, still among a small number. (AUDIO: Memory Lane)

21st century
According to the Seventh Doctor, the 21st century was "a little better" than the last century, in terms of transgender rights. (AUDIO: The Jabari Countdown)

By this time, women could be doctors, (TV: Smith and Jones) political candidates, (TV: Boom Town, The Christmas Invasion) police officers (TV: Everything Changes, The Woman Who Fell to Earth) and homeowners of their own right. (TV: The Eleventh Hour) Indeed, "a woman [could] do what she like[d]", (TV: The Shakespeare Code) and in some respects, had something like "equal rights" to men. (TV: To the Last Man)

Nevertheless, sexism was an ongoing issue, (TV: Smile) and many sentiments from the 20th century carried through to the new millennium. (AUDIO: Golden Age) Clara Oswald asked the Eleventh Doctor if he had shut the TARDIS down to basic while she piloted because she was a girl. (TV: Journey to the Centre of the TARDIS)

Brands like Wolverine used ideas of masculinity to sell their products. (TV: Revenge of the Slitheen)

The idea of gendered clothing still existed in 2079. (TV: The Wheel in Space)

Beyond the 21st century
30th century culture did not make a fuss about assigned genders. Chris Cwej, who was from this century, was unwavered when he found out that Eleanor Blake was a trans woman, facing violence and discrimination in the 20th century. He explained to her that "it seems a bit stupid to care about little stuff like that", considering the breadth of the universe, and all the dangers and variety to be found therein. (AUDIO: The Jabari Countdown)

Roz Forrester, similarly, from the same time period, had trouble understanding the racism and sexism she encountered in 1919 Paris, as such attitudes did not make it into the 30th century. (PROSE: Toy Soldiers)

51st century culture was very flexible around sexuality, (TV: The Doctor Dances) and, by extension, those "quaint little categories" which mattered in the early 21st. (TV: Day One) Jack Harkness had no trouble adjusting to using they/them personal pronouns for Orr, a Torchwood Three recruit with no fixed gender. Other members of Jack's team, native to 21st century Earth, took longer before they no longer stumbled. (AUDIO: Orr, Superiority Complex)

Gender roles on other planets
As Jo Grant encountered in her work with the Third Doctor, beings from other worlds were sometimes men, sometimes women, and sometimes neither. (AUDIO: The Hidden Realm) As on Earth, ideas and structures around gender varied from culture to culture.

For instance, systems of power could favour one gender over another. On Peladon, at the time Sarah Jane Smith visited, the ruler was always a man. Thalira was crowned Queen only because her father had no son, and even so it was mostly in title. Chancellor Ortron held the "real power". With encouragement from Sarah Jane, Thalira began to assert herself as ruler. (TV: The Monster of Peladon)

Adric, from a parallel 32nd century Alzarius, also differentiated between girls and women, and thought women were all "mindless, impatient and bossy". Nyssa called him a chauvinist for holding this position. (TV: Four to Doomsday)

On Necros, women's legs were to be covered at all times. Peri Brown, from 1980s Baltimore, thought this was "positively feudal". (TV: Revelatioon of the Daleks)

Formidians had a rigidly matriarchal culture, with even hiveless females outranking male drones in a Lyparian hive. They were led by a queen, and believed that males were not fit for combat. (AUDIO: Time in a Bottle)

On Terra Alpha, a pair of male roof-top snipers complained that women always got the better jobs, and the better guns. (TV: The Happiness Patrol)

Vilhol, of the Tenth Sontaran Battle Fleet from Sontar, believed that Leela, as a "human female", belonged to the "lesser gender" of a "lesser species", and would not accept help from her. (AUDIO: The King of Sontar) Staal, also of the Tenth Sontaran Battle Front, claimed that "words [were] the weapon of womenfolk" when he received verbal insults from Private Harris, judging him an unfit soldier. (TV: The Sontaran Stratagem)

Other Sontarans had no concept of gender, and either believed human women to be a separate species to men, (TV: The Time Warrior) or could not effectively distinguish humans based on apparent gender. (TV: The Snowmen, et al.) The Eleventh Doctor explained that "two genders are a bit further than [a Sontaran clone] can count", referring to Strax. (TV: The Snowmen) Indeed, Strax once mistook Henry Gordon Jago and Professor Litefoot for Madame Vastra and Jenny Flint, (AUDIO: The Haunting) and believed "Madame" was a rank. (PROSE: Silhouette)

Names and pronouns
Human names were often considered to be gendered, but some names, like Charley, Kim (AUDIO: Memory Lane) or Alex, were perfectly neutral. (AUDIO: The Havoc of Empires)

Though surnames could be passed on through marriage, (TV: Something Borrowed) the Fourth Doctor believed it was unusual for a husband to take on his wife's name. (AUDIO: The Crooked Man) Despite objections, the Eleventh Doctor preferred to think of Amy Pond's husband as "the new Mr Pond", (TV: The Big Bang, The Almost People) and decided that their daughter would be Melody Pond, rather than Williams. (TV: A Good Man Goes to War) Some opted to join their names together, as did William Stewart and Mary Lethbridge in 1603, becoming Lethbridge-Stewart. (PROSE: The Daughters of Earth)

Some titles, like "Miss" (PROSE: Silhouette) "Mrs", (AUDIO: Five Twenty-Nine) or "Madam", (TV: The Woman Who Fell to Earth) were strictly gendered, while others, like "Mx", (AUDIO: Superiority Complex, The Web of Time) or academic titles like "Dr" and "Professor" (TV: The Husbands of River Song, The Green Death) remained gender-neutral alternatives. (AUDIO: Five Twenty-Nine)

When spoken of in the third person, individual women were generally referred to with she/her pronouns, while individual men generally used he/him instead. (AUDIO: The Sword of the Chevalier) Those who did not fit neatly into either camp often used a gender-neutral alternative, like ze/hir (PROSE: Oblivion, War Crimes) or they/them. (AUDIO: Orr, et al.) Some people used different sets of pronouns at various points in their life, and the Tenth Doctor believed this ought to be respected. (AUDIO: The Sword of the Chevalier)

As he was often perceived as a man, (PROSE: Beltempest) the Eighth Doctor referred to himself as a "he; for now at least". (AUDIO: The Conscript) It took the Thirteenth Doctor time to get used to she/her pronouns — and other gendered language, like Madam — being directed at her as a result of her new appearance. (TV: The Woman Who Fell to Earth, The Ghost Monument, Rosa) Both incarnations confirmed that they were neither man nor woman, despite appearances. (PROSE: Interference - Book One, Beltempest, The Good Doctor)

Some who knew the Doctor well, like Jack Harkness (AUDIO: Piece of Mind) or River Song, would sometimes employ they/them pronouns to refer to the Doctor generally, (AUDIO: The Power of River Song, Concealed Weapon) or when unsure of incarnation. (AUDIO: Concealed Weapon) Similarly, Orr, a psychomorph with no fixed gender, used the personal pronoun "they", (AUDIO: Orr, et al.) and the title "Mx", (AUDIO: Superiority Complex) as did Mx Neon, a transtemporal museum curator. (AUDIO: The Web of Time)

When Jack Harkness referred to his Doctor using they/them pronouns, the Sixth Doctor assumed this future incarnation of his would be a woman, or at least tried to tease the information out of Jack by saying "she". Jack corrected him. (AUDIO: Piece of Mind)

Bernice Summerfield decided on "hir", over gendered pronouns like "him" or "her", to refer to Sgloomi Po, a Sloathe. (PROSE: Oblivion) Ossu-hir also used this set of pronouns after eating Issu-mul berries, and transforming from Ossu-male. (PROSE: War Crimes)

Humans from the early 21st century would often require time to learn gender-neutral language, and would tend to stumble over unfamiliar pronouns before getting used to them. (AUDIO: Orr, Superiority Complex) Yvonne Hartman, in part due to her personal relations skills, had no such qualms, and consistently used they/them for Orr before even first meeting them, having read the files. (AUDIO: Poker Face)

Behind the scenes
In the production notes of DWM 482, Steven Moffat suggested that River Song had been married 428 times, "one for each gender".