- disk (n.)
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- American English preferred spelling, 1660s, "round flat surface," from Latin discus "quoit, discus, disk," from Greek diskos "disk, quoit, platter," related to dikein "throw," from PIE *dik-skos-, from root *deik- "to show, pronounce solemnly; also in derivatives referring to the directing of words or objects" [Watkins]; see diction.
Sense of "phonograph disk" is 1888; computing sense is from 1947. Disk jockey first recorded 1941; dee-jay is from 1955; DJ is 1961; video version veejay is 1982. Disk-drive is from 1952.