soporific

adj. 催眠的，n. 安眠药

sonny, sonority, sonorous, sonorously, soon, sooner or later, soot, soothe, soothing, soothsayer, sooty, sop, sophism, sophist, sophisticate, sophisticated, sophistication, sophistry, sophomore, sophomoric, soporifically, soppily, soppiness, sopping, soppy, soprano, sorbet, sorcerer, sorcery, sordid, sordidly, sordidness, sore, sorely, soreness, sorghum, sorority, sorrel, sorrow, sorrowful,