/thuy'euh si nam"in, -sin"euh meen'/ , n. Chem.
a white, crystalline, water-soluble, bitter-tasting powder, C 4 H 8 N 2 S, occurring in mustard oil: used chiefly in organic synthesis. Also called allylthiourea .
[ 1850-55; THIO- + Gk sín ( api ) mustard + -AMINE ]