柯林斯词典sienna /sɪˈɛnə/ 1. N a natural earth containing ferric oxide used as a yellowish-brown pigment when untreated (raw sienna) or a reddish-brown pigment when roasted (burnt sienna) 生赭石 返回 sienna剑桥词典a type of soil that is used to colour paint 赭土（用作顔料） 返回 sienna