mainline
adjective uk/ˈmeɪn.laɪn/ us/ˈmeɪn.laɪn/
(COMMON)
usually US主流的（信念、方法等）
involving beliefs, methods, etc. that are most common
mainline churches 主流教会
the rivalry between catalog companies and mainline stores 目录公司和普通商店之间的竞争
(RAILWAY)
UK（铁路）干线的
relating to an important railway route between large towns or cities
Three mainline railway stations were closed because of bomb threats. 3个干线车站因炸弹威胁而关闭。
mainline
verb [ I or T ] slang uk/ˈmeɪn.laɪn/ us/ˈmeɪn.laɪn/
静脉注射（毒品）
to inject (= put into the body through a needle) drugs directly into the blood
Several of her friends were mainlining heroin. 她有几个朋友注射海洛因。
By now she was mainlining. 她至今仍在注射毒品。