Through the Looking Glass by Lewis Carroll.
"... There's glory for you!"
"I don't know what you mean by 'glory,' Alice said.
Humpty Dumpty smiled contemptuously. "Of course you don't -- 'till I tell you. I meant 'there's a nice knockdown argument for you.'"
"But 'glory' doesn't mean 'a nice knockdown argument,'" Alice objected.
"When I use a word," Humpty Dumpty said in rather a scornful tone, "it means just what I choose it to mean -- neither more nor less."