noun (used with a singular verb)
the branch of pharmacology dealing with the course of action, effect, and breakdown of drugs within the body.
Origin of pharmacodynamics
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(functioning as singular) the branch of pharmacology concerned with the action of drugs on the physiology or pathology of the body
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
The study of the action or effects of drugs on living organisms.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.