| Noun | 1. | hard disc - a rigid magnetic disk mounted permanently in a drive unitdisc drive, disk drive, hard drive, Winchester drive - computer hardware that holds and spins a magnetic or optical disk and reads and writes information on it magnetic disc, magnetic disk, disc, disk - (computer science) a memory device consisting of a flat disk covered with a magnetic coating on which information is stored removable disk - a hard disk that can be removed from the disk drive; removal prevents unauthorized use |