From Longman Dictionary of Contemporary Englishaltar boyˈaltar boy noun [countable] RRCa boy who helps a Catholic priest during a church service
Examples from the Corpus
altar boy• In grade school Gary had served as an altar boy.• When Michael had been an altar boy he had also stolen the lead from the church roof!• My boyfriend was an altar boy.• Yet he ended his days at daily mass, even serving for the priest when the altar boy of the day overslept. 