day off 
noun (plural days off)
A day’s holiday from work or school, on what would normally be a working day: it’s her day off today...
- People were working their days off and cancelling holidays to make themselves available for work.
- As I had a day off today, the wife decided we should go to Dewsbury for a few things then go for a walk in Crows Nest park.
- Big Sis has the day off work today, so we're soldiering on over to Southfork Ranch.