TK

TK means “to come”. You’ll typically see it as “TKTK” or “TKTKTK”, as a simple way to search (i.e., ⌘+f) for details that haven’t been written yet. I use it when drafting blog posts to skip over a sentence or section I want to come back to write later, to avoid losing momentum.

I didn’t learn this today, but within the last year or two (not too sure where!); I was just reminded by seeing it in print¹ in my library’s edition of Jez Burrow’s Dictionary Stories, which is otherwise lovely so far.