Of uncertain origin. Perhaps from Old Norse skjóta (“to shoot”), or perhaps related to Middle English scottlynge (“moving one's feet quickly, scampering”, literally “scuttling”), see scuddle, scuttle.
(intransitive, often with over) To move sideways (especially along a seat for multiple people), usually to make room for someone else (to sit, stand, etc.).
5transitiveTo dispatch someone or something at speed; Synonym of shoo.