hard disk
compound.compound. the part inside a computer that stores all your files, photos, and programs permanently.
compound. a rigid magnetic disk on which digital data is stored. It serves as the primary non-volatile storage device in most personal computers.
My hard disk is almost full because of all these videos.
You should back up your files to the cloud in case your computer's hard disk fails.
While solid-state drives are faster, traditional hard disk technology remains a cost-effective solution for storing massive amounts of data that do not require instant access.
A compound of the adjectives hard and disk, coined to distinguish the rigid magnetic storage platters from the flexible, plastic floppy disks that preceded them.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Often used interchangeably with 'hard drive' in casual conversation.
Last updated July 22, 2026