1. Also called sabbat'ical leave'. (in a school, college, university, etc.) a year, usually every seventh, of release from normal teaching duties granted to a professor, as for study or travel.
2. Chiefly Biblical.a yearlong period to be observed by Jews once every seven years, during which the fields were to be left untilled and all agricultural labors were to be suspended. Lev. 25. Cf. jubilee (def. 6).