vanguard vanguard /ˈvænˌgɑːrd/

noun

1. () The leading units moving at the head of an army  ( van , vanguard )
   the leading units moving at the head of an army
   
2. The position of greatest importance or advancement; the leading position in any movement or field  ( forefront , vanguard , cutting edge )
   the position of greatest importance or advancement; the leading position in any movement or field
    The Cotswolds were once at the forefront of woollen manufacturing in England
   the Cotswolds were once at the forefront of woollen manufacturing in England
    The idea of motion was always to the forefront of his mind and central to his philosophy
   the idea of motion was always to the forefront of his mind and central to his philosophy
   
3. Any creative group active in the innovation and application of new concepts and techniques in a given field (especially in the arts)  ( avant-garde , new wave , van , vanguard )
   any creative group active in the innovation and application of new concepts and techniques in a given field (especially in the arts)