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mess-dos: /mes·dos/, n.

[semi-obsolescent now that DOS is] Derisory term for MS-DOS. Often followed by the ritual banishing “Just say No!” See MS-DOS. Most hackers (even many MS-DOS hackers) loathed MS-DOS for its single-tasking nature, its limits on application size, its nasty primitive interface, and its ties to IBMness and Microsoftness (see fear and loathing). Also mess-loss, messy-dos, mess-dog, mess-dross, mush-dos, and various combinations thereof. In Ireland and the U.K. it is even sometimes called ‘Domestos’ after a brand of toilet cleanser.