Pronoun

Pronouns were words used to refer to an individual based on their gender, or lack thereof.

After the Doctor regenerated into a woman for the first time, Encyclopedia Gallifreya pondered as to how to approach the use of male and female pronouns in their data, wondering whether or not they should go through every entry about the Doctor and change every "he" to "she". (PROSE: Citation Needed)

Alex made sure to get the right pronoun as he translated the Sycorax leader's message "surrender or they will die." As it turned out, "they" referred to the population of humans with A-positive blood. (TV: The Christmas Invasion)

Behind the scenes
As far as this site is concerned, the Doctor's pronouns depend upon the context. Male and female pronouns are generally used to refer to the Doctor in a specific incarnation; the Doctor's first twelve numbered incarnations, plus the War Doctor, are male, using "he" and "him" pronouns, while the Thirteenth Doctor, a female, uses "she" and "her". When referring to the Doctor as an overall individual with no specific incarnation in mind, "they" and "them" are the generally accepted pronouns.