Meta is when things in fiction reflect real life, sort of like breaking the fourth wall or life imitates art... I'm not sure how to explain in the best terms, a google would do it 👍🏼
An example would be if a character in a show recognizes himself as an actor in the real world, like Shiva watching Pandya Store and complimenting KD's acting... or an intersection between real and reel. Basically you use the term to refer to anything that blurs the lines bw/connects reel and real.