In “I’ll Give You My Word,” by Diana Wynne Jones, Jethro’s little brother has a habit of looking angelic and egg-shaped while he spouts wonderful nonsense.
“Ponderous plenipotential cardomum,” he would say. “In sacks.” And after a bit, “Sentenious purple coriander.”
“Does that come in sacks too?” Jethro asked him.
“No,” Jeremy said. “In suitcases.”
This worries Jethro, on top of all the other things he worries about. School, tests, and the sources of Jeremy’s vocabulary in the many dictionaries in the house. Amidst all this word play, their parents are busy trying to find the source of unpleasant spells afflicting their clients. The two threads of the story meet in an amusing demonstration of the magic of words.
Some people say they get their ideas from Schenectady. This one must have come from Llanfairpwyllgwyngyllgogerychwyrndrobwllllantysiliogogogoch.