Nonsexist Language in Style Guides + Dictionary, May 2021, excerpts from webpages 

APA, Publication Manual of the American Psychological Association, 7th Edition 

- APA endorses the use of “they” as a singular third-person pronoun. This means it is officially good practice in scholarly writing to use the singular “they.” 

- When readers see a gendered pronoun, they make assumptions about the gender of the person being described (Gastil, 1990; Moulton et al., 1978). APA advocates for the singular “they” because it is inclusive of all people and helps writers avoid making assumptions about gender.

- When referring to a generic person whose gender is unknown or irrelevant to the context, use the singular “they” as the pronoun. For example, if you use nouns like “person,” “individual,” or “everyone” or phrases like “every teacher” or “each nurse” in a sentence, use the appropriate form of the pronoun “they” as needed.


Modern Language Association, MLA Handbook, 8th edition (9th edition pub Apr 2021)

Because it lacks grammatical agreement, this use of singular they has been considered a less desirable option than revising to use the plural or rephrasing without pronouns. But it has emerged as a tool for making language more inclusive (see “Guidelines”), and the MLA encourages writers to accept its use to avoid making or enabling assumptions about gender.


Associated Press, AP Stylebook, 55th edition

A new entry recommends gender-neutral language when possible. 

We also say: Balance these aims with common sense, respect for the language, and an understanding that gender-neutral or gender-inclusive language is evolving and in some cases is challenging to achieve.

Chicago Manual of Style, 17th edition

Because these pronouns [he, his, him] are also masculine-specific, they have in recent years been regarded as sexist. See CMOS 5.250, under “he or she”: To avoid sexist language, many writers use this alternative phrasing (in place of the generic he). Use it sparingly—preferably after exhausting all other, less obtrusive methods of achieving gender neutrality. In any event, he or she is much preferable to he/she, s/he, (s)he, and the like.” For more advice, including nine tips for achieving gender neutrality, see 5.251–61, especially 5.255.

American Medical Association, AMA Manual of Style, 11th edition

Avoid sex-specific pronouns in cases in which sex specificity is irrelevant. Do not use common-gender pronouns (eg, “s/he,” “shem,” “shim”). Reword the sentence to use a singular or plural non-sex-specific pronoun, neutral noun equivalent, or change of voice; or use “he or she” (“him or her,” “his or her[s],” “they or their[s]”). The use of the “singular they” construction is permitted when rewriting would be awkward or unclear. 


Merriam-Webster dictionary, Merriam-Webster.com

Definitions of “they”

3a —used with a singular indefinite pronoun antecedent

No one has to go if they don't want to.

b —used with a singular antecedent to refer to an unknown or unspecified person

An employee with a grievance can file a complaint if they need to.

c —used to refer to a single person whose gender is intentionally not revealed

A student was found with a knife and a BB gun in their backpack Monday.

d —used to refer to a single person whose gender identity is nonbinary

I knew certain things about … the person I was interviewing.… They had adopted their gender-neutral name a few years ago….