firing line

English Thesaurus

1. the most advanced and responsible group in an activity (noun.group)

hypernym	:	class, social class, socio-economic class, stratum,
definition	:	people having the same social, economic, or educational status (noun.group)

2. the line from which soldiers deliver fire (noun.location)

hypernym	:	line,
definition	:	a fortified position (especially one marking the most forward position of troops) (noun.location)