The academic year is divided up into three terms: Michaelmas Term, Hilary Term and Trinity Term. Terms are made up of eight weeks running from Sunday of 1st Week to Saturday of 8th Week, although undergraduate students are expected to be in College by Noon on Thursday of 0th Week (collections are held for most undergraduates on Friday and Saturday of 0th Week).
Students may arrive in College from Sunday of 0th Week prior to each term and must vacate their room by 10am on Saturday of 8th Week.
In Michaelmas Term, undergraduate Freshers should arrive on Monday of 0th Week for their first year of study.
The dates of full term can be found on the University of Oxford website.