shelfback noun2 •The vertical surface forming the back of a shelf.She came home later that day from Mrs. Rafferty's with a blue platter, which she placed standing up against the shelfback in the linen closet. — 2001 •The spine of a book.There was the man who collected any old volumes on etymology. There was a collector of books with gilded Victorian shelfbacks. — 1934 formsshelfbacks
