超二级结构super-secondary structure
再侵染源secondary source of infection
次生鳃secondary branchia
副电池by-pass accumulator【电】;secondary cell【电】
继发腭secondary palate
【计】 辅助网络支援secondary network support
第一、二、三产业primary, secondary and tertiary industries
【医】 仲酰胺secondary amide