1. 递减型：杂音有的开始时较强而后逐渐减弱到消失称为递减型(decrescendo)如主动脉瓣关闭不全的舒张期杂音及二尖瓣关闭不全的收缩期杂音. 有的则开始时较弱而后逐渐增强,然后又逐渐减弱到消失,称为递增递减型,如主动脉瓣狭窄的收缩期杂音.
2. (缩写为decresc.)渐弱：Crescendo (缩写为cresc.)渐强 | Decrescendo (缩写为decresc.)渐弱 | Diminuendo (缩写为dim.)渐弱
3. 渐弱：decres hisi 中间裁定 | decrescendo 渐弱 | decrescent 渐减的
4. 减弱：decrescence 苍白 | decrescendo 减弱 | decrial 诋毁
noun
verb
1. grow quieter
e.g. The music decrescendoes here
adj