turnovern.1. The act or result of turning over; an upset; as, a bad turnover in a carriage.()2. A semicircular pie or tart made by turning one half of a circular crust over the other, inclosing the fruit or other materials; as, an apple turnover.()3. An apprentice, in any trade, who is handed over from one master to another to complete his time.()a. Admitting of being turned over; made to be turned over; as, a turnover collar, etc.()