19th century US. Probably an alteration of British dialect scaddle (“to run off in a fright”), from the adjective scaddle (“wild, timid, skittish”), from Middle English scathel, skadylle (“harmful, fierce, wild”), perhaps of Scandinavian origin, from Old Norse *sköþull; or from Old English *scaþol, *sceaþol (see scathel); akin to Old Norse skaði (“harm”). Possibly related to the Greek σκέδασις (skédasis, “scattering”), σκεδασμός (skedasmós, “dispersion”). (US) Possibly related to scud or scat.
- (move or run away quickly): flee, vamoose, scat, take off, make tracks, get lost, kick rocks, hightail
- 1897, Hunter, Robert, and Charles Morris, editors, Universal Dictionary of the English Language, v4, p4291: "Etym. doubtful; perhaps allied to scud. To betake one's self hurriedly to flight; to run away as in a panic; to fly in terror. (A word of American origin.)"
- “Skedaddle” in Michael Quinion, World Wide Words, 7 February 2004.