[thahy-oh-yoo r-uh-sil]

noun Pharmacology.

a white, slightly water-soluble, bitter, crystalline powder C4H4N2OS, used chiefly in treating hyperthyroidism by reducing the activity of the thyroid gland.

Origin of thiouracil

First recorded in 1940–45; thio- + uracil Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for thiouracil



a white crystalline water-insoluble substance with an intensely bitter taste, used in medicine to treat hyperthyroidism; 2-thio-4-oxypyrimidine. Formula: C 4 H 4 N 2 OS

Word Origin for thiouracil

from thio- + uracil (uro- 1 + ac (etic) + -il -ile)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

thiouracil in Medicine




A white crystalline compound that interferes with the synthesis of thyroxine, used to reduce thyroid gland activity, especially in the treatment of hyperthyroidism.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.