I haven’t read the Harry Potter series but am familiar with the name Hogwarts and was surprised to come across it in my reading of Finnegans Wake this morning (pp.296):
“But, yaghags hogwarts and arrhquinonthiance, it’s the muddest thick that was ever heard dump since Eggsmather got smothered in the plap of the pfan.”
Rowling apparently isn’t sure where she got the name, but speculates it’s from Hogworts. As for Joyce, wiki says that this herb is used as a laxative, which I would guess is the reason for his interest — “the muddest thick that was ever heard dump.”
.i`` * ^ / . . . . . ` `~ 