1) This was the word for an apprentice whose indentures were transferred to another master, for whatever reason.
It is used in those records of the Cutlers’ Company which have to do with breaches of the rules: 1736 Three pounds was paid by Thomas Hancock of Attercliffe for takeing Samuel Birds, the apprentice of Samuel Eardley as a Turnover, his said Master being then living. Less commonly it was used as a verb: 1640 the peticon of John Shemelde, an apprentice to Stephen Metcalfe of Sheffield, cutler, alledgeinge that his maister lyes in prison at London … and desireing that he may be turned over to some other of the same trade, so that he may not loose his tyme.