1. front (def. 9).
2. the visible forefront in any action, activity, or field: TV reporters are constantly involved in the front line of events. 3. Football.See front four. 4. Basketball.See front court (def. 2b).
Pronunciation: (frunt'līn"),[key] —adj. 1. located or designed to be used at a military front line: a front-line ambulance helicopter. 2. of, pertaining to, or involving the forefront in any action, activity, or field: a front-line TV reporter. 3. highly experienced or proficient in the performance of one's duties.