So, I've heard the term x-adjacent to basically mean "this person disagrees with my views even though he's not y thing I hate". The problem is, where was this first used after 2014 GG?

I've never, EVER heard this term used unironically until around 2016-ish, and it's ONLY ever fucking used by leftists to shove people who are moderates into imaginary groups. A kind of scarlet letter to brand you as a bad person without directly saying it.

Like I legit want to know when it started being used - it's now part of the left wing newspeak to attack others for wrongthink, so I'm wondering was this used in an academic paper somewhere, or was it popularized on degenerate sites like Tumblr or Twitter or what. I am legitimately curious because it drives me absolutely nuts because the only fucking time I used this term before was to talk about things PHYSICALLY being next to each other, never as an ad hominem attack for an ideology.