A paperback is a book with a thin cardboard or paper cover. Compare hardback. She said she would buy the book when it comes out in paperback. a book with a stiff paper cover hardback
the book issue where heavy paper or thin card is used in place of boards, in many formats and unless otherwise described to be assumed to be in mass market format, UK size about 7 x 4¼ (see also trade paperback)
A binding with a soft cover, usually a light cardboard A trade paperback is usually the same size as a hardcover book, and printed to the same standards A mass-market paperback is usually smaller, designed to fit in a rack, and printed on cheaper paper