S0536300 (sôft′bound′, sŏft′-)adj. Not bound between hard covers: softbound books.
pa•per•back
(ˈpeɪ pərˌbæk)
n. 1. a book bound in a flexible paper cover. adj. 2. (of a book) bound in a flexible paper cover. 3. of or pertaining to paperbacks. Compare hardcover. [1895–1900]AcronymsSeesoybeanThesaurusSeepaperback