No. I will guess it has something to do with turtles singing. 
Ooh, I bet that’s the line that’s trying to become an earworm type obession. I was thinking reworded Christmas Carols–you know, where “Earth” becomes “terrestrial sphere” type thing as where I was familiarish with the word, but “Cats” is even more likely.
Yes, from reading a book on Greek mythology as a child.
No clue.
I do recall the phrase terpsichorean cacaphony (wonderfully alliterative) however, but I have no memory of what that means either.
And their cousin, Burpsichore, was the patron goddess of Tupperware.
Without reading the thread: Yes.
Of course, I’ve played the Cats soundtrack too many times. It’s mentioned in the song Mr. Mistoffoles. It’s not something I could have worked out otherwise.
Damn straight. Terpsichore, muse of dance.
Best use: TS Elliot
They’re quiet enough in the morning hours,
they’re quiet enough in the afternoon,
reserving their terpsichorean powers
to dance by the light of the Jellicle Moon.
Also, I was the kind of kid who read the dictionary for kicks.
Heh, I knew it too. Feeling quite pleased with myself now.
No. No idea. Not even close.
I knew, but (a) I’m an enormous geek, and (b) I’m working on a fantasy novel about a world populated with mythological creatures, so for quite some time I’ve been immersing myself in mythology. Thus I knew off the top of my head that Terpsichore is the muse of dance, which made the answer obvious.
Wait…wasn’t “Terpsichorean” referred to in some T S Eliot work or something?
I’ve scanned the whole thread and I just can’t find it!
Ah, yes. Sorry I missed that.
See Post #67 a few above you.
I knew the word - just 'cuz it’s, well, a cool word. Same with *crepuscular*and callipygian and stuff like that…I especially like callipygian. 
April 1st is the cruelest day