The origin of the editor’s mark “TK” is murky. It’s what you write when there’s a fact or addition you’re waiting on. Instead of stopping everything, simply type “TK” and you know you can come back and fix it later.
The modern purpose of TK is that there are few words in English that contain these two letters juxtaposed in this way, so it’s super easy to use Word to search your manuscript. (Except for ‘latkes’ and ‘pocketknife.’) But I think it predates search.
The magic of TK is more interesting. The existence of TK means we don’t have to stop and wait for everything to be perfect before we proceed.
If the flooring for the kitchen hasn’t arrived yet, TK and then move on to wallpaper the dining room.
Our lives are filled with TK moments. It’ll come. No need to stop and wait for it.