- jockey
- 1529, "boy, fellow," originally a Scot. proper name, variant of Jack. The meaning "person who rides horses in races" first attested 1670.
- disk
- Amer.Eng. preferred spelling, 1660s, from L. discus "quoit, discus, disk," from Gk. diskos, from dikein "throw." Sense of "phonograph disk" is 1888; disk jockey first recorded 1941; dee-jay is from 1955; DJ is 1961; video version veejay is 1982. Computing sense is from 1947; Disk-drive is from 1952.