Google News feed shows me the following.
What does the term "Super Worm Equinox Moon" mean and has it ever been used before this 2019 clickbait instance?
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All those adjectives being smooshed together signify an uncommon event. That's why you've never seen them together like that before.
All 3 conditions have to hold true:
It's a supermoon, which means the full moon coincides with the moons perigee or nearest approach. That can make it appear up to 30% brighter than one at apogee (farthest away). These happen about every 13 months and it doesn't have to be exact so usually, we get 2 of them in a row, like we did this year. February had a supermoon and so did March.
It's a worm moon, which means it is occurring in the month of March (see @astrosnapper's answer for a better explanation of that).
It's during an equinox, basically the first day of spring (or autumn).
If any one of those isn't happening then it can't be called a Super Worm Equinox Moon.
Apparently, the term supermoon (all one word, by the way) is a relatively recent thing. I tried to view it on Google N Gram viewer, but...
It is a particularly bright full moon and it does deserve to have its own terminology, IMO.
Update: The rarity of the event is certainly relative. I saw a tweet from National Geographic that we also had a super worm equinox moon 19 years ago.
All the monthly Full Moons are named e.g. list at timeanddate.com, of which "Harvest Moon" is the one people are probably most familiar with. So the March Full Moon is indeed the "Worm Moon" although rarely referred to as such. The extra hyperbole ("Super", "Blood" etc) seems to be a recent (within the last few years) media phenomenon for unknown reasons...
A supermoon is when the full moon occurs at the time when the moon is at its closest point to us in its elliptical orbit. This means that the moon is slightly bigger (honestly, you wouldn't notice it unless you made careful comparisons) and a chunk brighter than normal full moons. Except that supermoons happen three or four times every year, so, actually, a supermoon is itself a pretty normal full moon.
In the last few years, the media seems to have latched onto these as EXCITING! EVENTS!, despite the fact that they account for about a quarter of all new moons. In the last year or so, perhaps they sensing that we have supermoon fatigue ("What, another one? There was a supermoon only a couple of months ago..."), they've started putting long chains of adjectives in front of the word "supermoon" to make it sound EVEN! MORE! EXCITING!!1! These adjectives mostly come from traditional names for each month's full moon, but they sound NEW! and EXCITING!! because we don't use them very often in the modern era.