Welcome, dear readers, as always. I’ve been teaching the Odyssey again and, as I am hardly the first to say (about the ten millionth, at least, I’d guess, from its initial general circulation, probably in the 4th to 3rd centuries BC): “Every time I read it, I find something new.”
In this case, it was in a passing remark made by Odysseus to his Phaeacian hosts while telling them the long story of “How I Still Haven’t Gotten Home”. We are in Book 12 and Odysseus and his men are on the ill-fated island of Thrinakia (“Tridentia” in English) where Helios keeps his pet cattle.

and flocks and from which Odysseus has been warned away by Circe.

Odysseus and his men have dragged their ship ashore to a cave “there where the pretty dancing places of the nymphs and [their] seats were”. (Odyssey, Book 12, line 318, my translation)
In the early Greco-Roman world, it was believed that there were spirits in everything and “nymph” had a wide meaning, from those who lived in springs, Naiads,

(This is from the story of the Golden Fleece, where Herakles’ companion, Hylas, is abducted by several naiads as he tries to get water from a spring.)
to those who lived in trees, Dryads and Hamadryads,

(This is a very spooky and convincing work by SamanthaCatherine at Deviant Art. Here’s her website: https://www.deviantart.com/samanthacatherine )
to those who live in the sea, Oceanids and Nereids.

In the line quoted, there is simply the word “of nymphs”, but, as there is a cave, and a similar cave on Ithaka, in Book 13, has Naiads, (Odyssey, Book 13, lines 347-348) I’m going to guess that these are Naiads, too.
The word for “dancing places” is, transliterated, khoroi, and it can also mean “round dances”, suggesting that the nymphs were doing what in the South Slavic world is called the kolo

or in modern Greece, a syrtaki,

although both of these may also be danced in a line. And we can see the suggestion of this round pattern in ancient illustrations, like the so-called “Borghese dancers”, from the 2nd-3rd century AD—

(A later plaster copy)
But the idea of supernatural dances to me suggests another tradition, that of “fairy rings”.

Who these fairies were isn’t an answerable question. Perhaps the descendants in belief from the ancient idea of spirits in everything? Certainly they dance in circular patterns like the nymphs on Odysseus’ Ithaka,

but, in this later tradition, unthinking people can be lured into such rings and be made to join in the dancing till they not only lose track of time, but lose time itself—a common motif about mortals who enter the Otherworld. In more modern times, W.B. Yeats (1865-1939) included the idea in his long poem, The Wanderings of Ossian (1889), and C.S. Lewis (1898-1963) has visitors to Narnia find that there is a great difference between time back home in England and that in Narnia.
As one illustration, here’s a late appearance of the idea—in comic form–in Basil Hood and Arthur Sullivan’s (completed by Edward German after Sullivan’s death) operetta, The Emerald Isle (1901).

The story, set in 1801 in Ireland, is a complicated one with Irish rebels (or patriots, depending) and the British Lord Lieutenant and his redcoats. Into the middle of it comes Professor Bunn,

who appears to be pulled back and forth between the two sides. At one point, however, he is on the Irish side and, disguised as an ancient man,

he tries to scare off the redcoats by telling them what happened to him when he was lured into such a ring.
“BUNN. Many years ago I strode
Down the Carrig-Cleena road;
Night coming on, tired out, I lay
Where the legend says the fairies play!
But the tales I had heard of fairy tricks
Were never believed by me;
Then I was a youth of twenty-six,
But now I’m eighty-three!
ALL. Now he’s eighty-three!
BUNN. Round and round the fairy ring,
There I heard the fairies sing;
This is the fairy song I heard,
Do I remember it? — every word.
Da Luan, da mort, da Luan, da mort
Angus da Dardine!
Many, many people may
Disbelieve what I do say —
Once I was young and foolish, too,
And an ignoramus, just like you;
But whenever you hear of fairy tricks,
Don’t laugh at ’em any more.
Then I was a youth of twenty-six,
But now I’m ninety-four!
ALL. Now he’s ninety four!
BUNN. Dancing round the fairy ring
All that time I’ve had to sing;
Though you may not believe a word,
This is exactly what occurred,
Da Luan, da mort, da Luan, da mort
Angus da Dardine!”
(The words to the fairies’ song are almost as mysterious in English as they’re meant to sound in Irish: “Monday, Tuesday, Monday, Tuesday, and Wednesday!” These words appear to be taken from a well-known Irish folktale, “The Legend of Knockgrafton”, where they are spelled in this fashion, including some spelling mistakes. In Modern Irish, this would be “De Luain, De Mairt, De Luain, De Mairt, agus De Ceaodaoin”. Thomas Crofton Croker (1798-1854) first published it in Fairy Legends and Traditions of the South of Ireland, 1825. This went through many editions, but you can read it yourself in the second edition of 1838 here: https://archive.org/details/fairylegendstrad00crokiala/page/n7/mode/2up If you’d like to hear this sung—and I recommend it for its jaunty little tune–go to: https://www.youtube.com/watch?v=-t6Q9aAmhcA and run it over to about 6:28. At the moment, there’s no professional recording, but this was a production by The Prince Consort in 1982 which is on Pearl CD Gems 0189, along with a previous late Sullivan work with Basil Hood, The Rose of Persia. )
Odysseus seems to assume that nymphs and their dances are a natural part of the landscape and I imagine that so did the early audiences for the epic and from the songs and stories from which it came. Yeats claimed to believe in these Otherworld folk and included the Croker story in his Folk and Fairy Tales of the Irish Peasantry (1888). (You can read the book here: https://sacred-texts.com/neu/yeats/fip/index.htm You can also read it at the Internet Archive, but I wanted to give you this LINK because it puts you into the Sacred Texts site, which is full of good things for people interested in traditional stories.)
Unfortunately, modern science not only doesn’t believe in fairies, but explains fairy rings

as:
“a naturally occurring ring of fungi that can produce rings or arcs of dead grass, lush green grass that grows quicker than the rest of the lawn, or mushrooms.” (This is from the Garden Seeker website, under the title, “Fairy Rings in Your Lawn? How to Remove Them and Prevent Them Returning”.)
Spoilsports.
Thanks for reading, as always.
Stay well,
Avoid seductive circles, particularly under a full moon,

And know that, as ever, there’s
MTCIDC
O