secondary dam副坝secondaryadj.次要的；从属的；中等教育的n.副手；次要位置secondary structure次级结构,二次结构,次生结构secondary filtering二次滤波secondary batteries蓄电池Secondary elarifier二沉池secondary gyroscope进动陀螺仪,阻尼陀螺仪,二自由度陀螺仪secondary condenser次级冷凝器secondary schooling中等教育secondary quartzite次生石英岩secondary equipment二次设备secondary kill mode二次杀伤