Definition of "meta"

meta¹

/ˈmɛtə/

adjective
comparative more meta, superlative most meta
1. (informal) Self-referential; structured analogously (structured by relationships), but at a higher level.
  Quotations
  […] in finessing obligations you fail a "meta" kind of obligation.
  2002, Robert C. Neville, Religion in Late Modernity‎, page 31
  Besides, I can just hear Vaughan: "Very funny, Stacey, very Charlie Kaufman-esque, very meta, very '97. I can't use it."
  2006, Brendan Vaughan, What Would MacGyver Do?‎, page 186

meta²

/ˈmiːtə/

noun
plural metas or metae
1. Boundary marker.
2. (historical) Either of the conical columns at each end of an Ancient Roman circus.

meta³

/ˈmɛtə/

noun
countable and uncountable, plural metas
1. (video games) Short for metagame.
2. (by extension, countable, Internet slang) An informal but widely adopted practice in a given field; a de facto standard.
  Quotations
  I remember interviewing PewDiePie a few years ago, and he was sort of telling me about this time where it was like edgy videos were being really rewarded, so everyone was kind of chasing like edgy humor and edgy memes, and sort of trying to figure out where the edge was. And then YouTube changed the meta, and suddenly, it wasn’t good to be edgy, you weren't weren’t going to make as much money or get as many views.
  2023 October 27, 29:51 from the start, in Hard Fork‎ (podcast), spoken by Kevin Roose, The New York Times
adjective
comparative more meta, superlative most meta
1. (video games) Prominent in the metagame; effective and frequently used in competitive gameplay.

meta⁴

/ˈmɛtə/

noun
plural metas
1. (informal) Metoidioplasty.