papaverine
noun
pa·pav·er·ine pə-ˈpa-və-ˌrēn 
-ˈpav-rən,
-ˈpa-və-
: a crystalline alkaloid C20H21NO4 found in opium or made synthetically that is used usually in the form of its hydrochloride chiefly as an antispasmodic for its ability to relax smooth muscle
Example Sentences
Recent Examples on the Web The wife had donated her organs, and papaverine had been used. 
Faye Flam, Philly.com, 6 Sep. 2017
Faye Flam, Philly.com, 6 Sep. 2017 Word History
Etymology
International Scientific Vocabulary, from Latin papaver poppy
First Known Use
1848, in the meaning defined above
Medical Definition
papaverine
noun
pa·pav·er·ine pə-ˈpav-ə-ˌrēn -(ə-)rən
-(ə-)rən : a crystalline alkaloid C20H21NO4 that constitutes about one percent of opium, that is made synthetically from vanillin, and that is used usually in the form of its hydrochloride C20H21NO4·HCl especially as a vasodilator because of its ability to relax smooth muscle