Disk Operating System

n. type of computer operating system, DOS

Disk Operating System (specifically) and disk operating system (generically), most often abbreviated as DOS (not to be confused with the DOS family of disk operating systems for the IBM PC compatible platform), refer to operating system software used in most computers that provides the abstraction and management of secondary storage devices and the information on them (e.g., file systems for organizing files of all sorts). Such software is referred to as a disk operating system when the storage devices it manages are made of rotating platters (such as hard disks or floppy disks).
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Noun
1. an operating system that is on a disk
(synonym) DOS
(hypernym) operating system, OS
(hyponym) MS-DOS, Microsoft disk operating system

disk operating system, DOS, type of computer operating system (Computers)

<operating system> (DOS) The original disk operating system from IBM.
DOS was the low-end OS of choice on the IBM 360, the high-end system was called just "OS". DOS had a smaller kernel and less fu

<operating system> (DOS) The name of a number of operating systems which include facilities for storing files on disk. Such a system must handle physical disk I/O, the mapping of file names to disk addresses and protection of files from unauthorised access (in a multi-user system).