the leaders of a movement in society, for example in politics, art, industry, etc. （政治、艺术、工业等社会活动的）领导者，先锋，先驱者 the part of an army, etc. that is at the front when moving forward to attack the enemy 先头部队；前卫；尖兵 The army was advancing steadily and the vanguard was already at the border. 军队稳步前进，先头部队已经到达边境。
Word Originlate Middle English (denoting the foremost part of an army): shortening of Old French avan(t)garde, from avant ‘before’ + garde ‘guard’.