(computing) Also called magnetic disk, hard disk. a direct-access storage device consisting of a stack of plates coated with a magnetic layer, the whole assembly rotating rapidly as a single unit. Each surface has a read-write head that can move radially to read or write data on concentric tracks Compare drum1 (sense 9) See also floppy disk
Amer.Eng. preferred spelling, 1660s, from L. discus "quoit, discus, disk," from Gk. diskos, from dikein "throw." Sense of "phonograph disk" is 1888; disk jockey first recorded 1941; dee-jay is from 1955; DJ is 1961; video version veejay is 1982. Computing sense is from 1947; Disk-drive is from 1952.