—n. 1. the shape and size of a book as determined by the number of times the original sheet has been folded to form the leaves. Cf. duodecimo, folio (def. 2), octavo, quarto. 2. the general physical appearance of a book, magazine, or newspaper, such as the typeface, binding, quality of paper, margins, etc.
3. the organization, plan, style, or type of something: The format of the show allowed for topical and controversial gags. 4. Computers.the arrangement of data for computer input or output, such as the number and size of fields in a record or the spacing and punctuation of information in a report.
—v.t. 1. to plan or provide a format for: to format the annual telethon. 2. Computers. a. to set the format of (input or output): Some word-processing programs format output in a variety of ways. b. to prepare (a disk) for writing and reading.