- mainstay (of something)
a person or thing that is the most important part of something and enables it to exist or be successful 支柱；中流砥柱 He is the mainstay of our theatre group. 他是我们剧组的台柱。 Cocoa is the country's economic mainstay. 可可是这个国家的经济支柱。 🔊🔊 Love songs form the mainstay of his act. 情歌是他表演的主体。