the.com/backup drive

means A separate storage device that keeps a duplicate copy of your files so you don't lose everything when your primary device fails.

from A compound of two plain English words rather than any ancient root: 'back up' as in reversing to a safe position, extended by the mid-20th century into computing jargon for making a protective copy of data, and 'drive' from the older mechanical sense of a spinning or driven mechanism, first used for the wheels of a vehicle and later borrowed for disk storage devices once hard disks became common in computers. Put together, 'backup drive' simply names the gadget whose job is to hold the spare copy — the etymology is functional, not poetic, which is rather fitting for something nobody thinks about until disaster strikes.