sb. Med. [a. F. calmant, pr. pple. of calmer; used as adj. and sb. in medical lang. and transferred.] = CALMATIVE sb.
1811. Melesina Trench, Rem. (1862), II. 210. What we females call work. It is a sort of composer, a calmant peculiarly useful, I believe, to the delicate and irritable spirits of women.
1862. Med. Times, II. 390/1. Tobacco has always had the reputation of being a calmant rather than a stimulant, and of, at the same time, increasing the power of mental concentration and abstraction.
1881. Mrs. C. Praed, Policy & P. (new ed.) xlii. 428. Prussic acid acted as a speedy calmant.