Dos

Part of speech: noun

Pronunciation: /duːz/

Definitions

1. A Spanish article used for masculine plural nouns; a term referring to the number 2; an acronym for an early computer operating system known for text-based interfaces
2. A definite article applied to multiple male objects or persons in Spanish; the numeric representation of the count immediately following one; historically, an abbreviation for Disk Operating System used in computing
3. Used in Spanish to denote more than one masculine noun; indicating the quantity second in a sequence; a name for an operating system prevalent in early personal computers based on command-line input

Etymology: The computing sense began as a nickname. In 1980, Tim Paterson, working for Seattle Computer Products, wrote a small operating system and called it QDOS, for "Quick and Dirty Operating System." Microsoft bought the system, renamed it 86-DOS and then MS-DOS, and supplied it with the IBM PC in 1981. The abbreviation itself stands for "disk operating system," a generic name rather than a brand. IBM had used the same phrase earlier, with DOS/360 in 1966 for its System/360 mainframes, so the term predates the personal computer by about fifteen years. The Spanish numeral "dos," meaning two, is an unrelated homograph from Latin "duos," and English has no connection to it.

Synonyms: doses, administrations, portions, quantities, measures