vacancy (n.)

1570s, "a vacating;" c. 1600, "state of being vacant," from Late Latin vacantia, from Latin vacans "empty, unoccupied," present participle of vacare "be empty," from PIE *wak-, extended form of root *eue- "to leave, abandon, give out." From 1690s as "a vacant office or post;" meaning "available room at a hotel" is recorded from 1953. Related: Vacance (1530s); vacancies.