Singular they

Singular they, along with its inflected or derivative forms, them, their, theirs, and themselves (also themself and theirself), is a gender-neutral third-person pronoun. It typically occurs with an indeterminate antecedent, to refer to an unknown person, or to refer to every person of some group, in sentences such as:

This use of singular they had emerged by the 14th century, about a century after the plural they.^[4][5][2] Singular they has been criticised since the mid-18th century by prescriptive commentators who consider it an error.^[6] Its continued use in modern standard English has become more common and formally accepted with the move toward gender-neutral language.^[7][8] Some early-21st-century style guides described it as colloquial and less appropriate in formal writing.^[9][10] However, by 2020, most style guides accepted the singular they as a personal pronoun.^{[11][12][13][14]}

In the early 21st century, use of singular they with known individuals emerged for non-binary people, as in, for example, "This is my friend, Jay. I met them at work."^[15] They in this context was named Word of the Year for 2015 by the American Dialect Society,^[16] and for 2019 by Merriam-Webster.^[17][18][19] In 2020, the American Dialect Society also selected it as Word of the Decade for the 2010s.^[20]