mess-dos

/mesdos/ , 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.