pron

• (the third-person plural nominative) A group of entities previously mentioned.
  "Fred and Jane? They just arrived."
• (the third-person singular nominative, occasionally proscribed) A single person, previously mentioned, whose gender is unknown, irrelevant, or (since 20th c.) non-binary.
  "Somebody requested a seat at Friday's performance but didn't say if they preferred the balcony or the floor."
• (indefinite pronoun, vague meaning) People; some people; people in general; someone, excluding the speaker.
  "They say it’s a good place to live."
• (indefinite pronoun) The authorities, the (power) elites, the powers that be, the establishment, the man, the system: government, police, employers, etc.
  "They'll tax us for the air we breathe next."

det

• (now Southern England dialect or nonstandard) The, those.
  "They rooks as you see … only coom a few year agoo."
• (US dialects, including African-American Vernacular) Their.
  "MARY ELLEN is a different case from the others. She has five children and, she claims: "I don't know who they father is. I ain't never kept track. They is always another one. You know, I can catch me a guy[.]""

verb

• (transitive) To refer to (someone, sometimes especially someone who does not use gender-neutral pronouns) using they/them pronouns.
  "I have a pin that says she/her, but I still get theyed all the time."

pron

• (US dialectal) There (especially as an expletive subject of be).
  "They’s music in the twitter of the bluebird and the jay."