[sop.o.rif.ic] adj [prob. fr. F soporifique, fr. L sopor deep sleep; akin to L somnus sleep--more at somnolent] (1665) 1 a: causing or tending to cause sleep b: tending to dull awareness or alertness
2: of, relating to, or marked by sleepiness or lethargy
[2]soporific n (ca. 1727): a soporific agent; specif: hypnotic 1