So I figured this one may be hard but I hope it has a good AHA moment and then (if you remember that this is a standard meta with usual metaisms) you can real it home safely. Once you get the aha, that's where all the difficulty is.
I thought of several ways I'd do this and considered even making a grid where all the clues were four letter words which would have been... well, trouble is the clues can't be precise that we. This grid has a few trouble corners where I had to make up absurd entries, but for the most part I tried really hard to make the clues straightforward.
Sort of a pre-nudge: I had originally intended to have a 16 x 16 grid where the lower right 15x15 were reasonable and symmetric "real" grid and the left and top edge would be assymettric four letter entries all with the clue "An arbitrary selection of four letter" (and I'd provide the letters). Then I thought I wouldn't need to. But I forgot I had a reason to.
Nudge 1: So there are 17 entries that are somehow grouped together in groups of four or five. They are the key. Figure out why they are grouped together
Nudge 2:Oh. It just occurred to me that some might assume that because the group entries are four in a group (except one that is five) that that might have something to do with four letter words. But the number of entries in each group is not relevant. It's not entirely a coincident must of them are four but it's not significant. Some of my earlier drafts had groups with only three or two entries but I didn't find them satisfactory.
Nudge 3: Again try to figure out why the entries are grouped together the way they are. Each grouping has something to do with four letter words and order.
Nudge 4 I said the answer is somewhat longer than average because I hate prompts that say something like "The meta is a 17 letter phrase".... But the meta is a 17 letter phrase.