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Winchester disk

noun Computers.
  1. a hard disk that is permanently mounted in its unit.

Origin of Winchester disk

First recorded in 1970–75; originally an IBM code name; the designation for a device containing two such disks was 3030 (each disk containing 30 megabytes), the same as the model number of a well-known Winchester rifle
Also called Winchester.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for winchester disk

Winchester disk

noun
  1. a type of hard disk in which disks are permanently sealed, together with read-write heads, in an airtight container to keep dust out

Word Origin for Winchester disk

C20: named after the 3030 Winchester rifle, as the original device would have had 3030 as its IBM number
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012