Caledfwlch
It is the eponym of Excalibur, from the "Sword in the Stone" story in Arthurian legend.
Person A: Hey, what was the sword in the Sword in the Stone story called again?
Person B: Well, its name in the story is Excalibur, but the name itself comes from a Welsh name — Caledfwlch.
Person A: Oh. I didn't need to know all that, but thanks anyway, I guess.
Person B: Well, its name in the story is Excalibur, but the name itself comes from a Welsh name — Caledfwlch.
Person A: Oh. I didn't need to know all that, but thanks anyway, I guess.