From Longman Dictionary of Contemporary Englishoff-dutyˌoff-ˈduty adjective BEif someone such as a policeman, nurse, or soldier is off-duty, they are not working an off-duty guard I shall be off-duty on Thursday.
Examples from the Corpus
off-duty• One result of devolving off-duty allocation to ward level may be arrangements which take too much account of staff interests.• Officers working off-duty are required to respond to crimes that occur at their job.• A jobless actor was annoying an off-duty bouncer, announcing loudly that he was due for a break.• The blaze was spotted by an off-duty fire-fighter.• He would have six off-duty hours, to use as he pleased.• Friends called Jensen an enthusiastic officer who supported youth sports in his off-duty hours.• Sorry, I'm off-duty now.• And even when he's off-duty, O'Neill happily embraces the aura of a man most would consider a burden.• They followed the raider then the off-duty policeman leaped out of the car and grabbed him. 