Mid is usually a term to describe something unsatisfactory. Weather that be the look of a bird on a night out, or the quality of chips at the local.
"Oh god the reply was mid, cheers Taya"
Something average, nothing special
Waiter: How did you like the food?
Gordon Ramsay: Eh, it was pretty mid.
It's another insult you say to something or someone but on a lower scale like saying some thing is stupid.
"Bro that looks so Mid to use"
"Bro that show is so Mid."
Lol JoJo Mid Adventures
A synonym for John Henry’s team, the Boston Red Sox, used to illustrate their uneventful and disappointing seasons.
“Did you go to the Red Sox game last weekend?” “Fuck no, why would I pay for overpriced tickets to watch a mid game?”