If your younger acquaintances start referring to you (or anything you do) as ‘mid’ they are not being polite. For Gen Z ‘mid’ now means ‘mediocre or low quality’. The hyper-hip, super-cool online Urban Dictionary says that ‘mid’ is ‘used as an insult to degrade an opposing opinion, labelling it average or of poor quality’. They say this word (used in this way) emerged into the language around July 2020. It seems that ‘mid’ is intended to be a shortening of the word ‘middle’. It was born in the pot smoking sub-community in the early 2000s. It that context it was used to mean marijuana that was average in potency or generally of average quality. Then starting around the early 2010s, ‘mid’ started to be used in a more general way to refer to average or mediocre things. These days, I am assured, ‘mid’ is used humorously. It is now meant to be a whimsical or jocular putdown – especially as a way to undercut something that others see as being excellent or of high quality. So, if a younger relative describes your opinions, your tastes, your politics (or anything else) as ‘mid’ the proper response from you would be: ‘Watch your tongue, youngster!’