hard drive

disk drive which reads and writes to a hard magnetic disk (Computers)

A hard disk drive (HDD), commonly referred to as a hard drive, hard disk or fixed disk drive, is a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces. Strictly speaking, "drive" refers to a device distinct from its medium, such as a tape drive and its tape, or a floppy disk drive and its floppy disk. Early HDDs had removable media; however, an HDD today is typically a sealed unit with fixed media.
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Noun
1. computer hardware that holds and spins a magnetic or optical disk and reads and writes information on it
(synonym) disk drive, disc drive, Winchester drive
(hypernym) drive
(part-meronym) hard disc, hard disk, fixed disk
(classification) computer science, computing

hard disk drive