The term 'in service' can refer to a variety of different job descriptions. The crossword solution for this term is 'USED', which can refer to a person who is employed in a particular field or profession. This could include someone who is employed in the military, law enforcement, or any other type of service-oriented job. It could also refer to someone who is employed in a customer service role, such as a waiter or retail associate. In any case, the term 'in service' implies that the person is actively employed in a particular field or profession.