community service 
noun [mass noun]
1Voluntary work intended to help people in a particular area: opportunities to engage in community service [as modifier]: she received a community service award...
- Dozens of people I know are involved in voluntary community service in one way or another, and seek no reward, nor even expenses.
- The community service award is for people or organisations who have helped to improve the quality of life for people in this town.
- Many are people nominated for their work in education, health, local sport and the area of community service.
1.1 English Law Unpaid work, intended to be of social use, that an offender is required to do instead of going to prison: [as modifier]: a community-service order...
- She was ordered to do community service for 100 hours and to pay £250 costs.
- Offenders on community service orders should be brought in to assist the clean-up.
- He's been sentenced to 120 hours of community service and been ordered to pay court costs.