Christopher Morley, The Haunted Bookshop (Edison: Castle Books, 2004; 1919), p. 170:
“All right,” said the bookseller amiably. “Miss Chapman, you take the book up with you and read it in bed if you want to. Are you a librocubicularist?”
Titania looked a little scandalized.
“It's all right, my dear,” said Helen. “He only means are you fond of reading in bed. I’ve been waiting to hear him work that word into the conversation. He made it up, and he's immensely proud of it.”