the first beat of a musical measure (as the conductor's arm moves downward)
downbeat详细解释
down.beat n.（名词）Music The downward stroke made by a conductor to indicate the first beat of a measure.【音乐】 强拍：乐队指挥向下的手势表示一个节拍的第一拍Informal A period of stagnation or inactivity.【非正式用语】 停滞：迟钝的或不活泼的期间adj.（形容词）Cheerless; pessimistic.忧郁的；悲观的
