Two and a half years after the Associated Press announced it would recognize they as a singular pronoun, America’s oldest dictionary is following suit. The Guardian reports that Merriam-Webster has officially added they into its online dictionary as a grammatically correct nonbinary pronoun.
Merriam-Webster notes in a blog post that people have been using they as a singular pronoun since the 1300s, and quoted an 1881 letter in which Emily Dickinson refers to a person of unknown gender with the pronouns they, theirs, and even themself. The post also mentions that using you as a singular pronoun wasn’t always considered grammatically correct, either: it was born out of necessity, gained popularity in casual conversation, and eventually became formally accepted as a singular pronoun.
Merriam-Webster does acknowledge that this new application of they differs from how the general public has most commonly used it in previous centuries. In the past, the singular they has referred to “a person whose gender isn’t known or isn’t important in the context.” For example, you would probably say “Tell each person that they are responsible for cleaning up their own trash,” rather than “Tell each person that he or she is responsible for cleaning up his or her own trash.” Now, however, we use they to describe a person who simply doesn't identify as either male or female.
It’s a much more direct use of the pronoun, and it’s this definition that Merriam-Webster is adding to the existing dictionary entry for the word they: “used to refer to a single person whose gender identity is nonbinary.”
[h/t The Guardian]