Definition of "prostaglandin" [prostaglandin]

• Any of a group of potent hormonelike substances that are produced in various mammalian tissues, are derived from arachidonic acid, and mediate a wide range of physiological functions, such as control of blood pressure, contraction of smooth muscle, and modulation of inflammation. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Also, semen has a substance in it called prostaglandin, which is the same thing your body makes to soften your cervix."
• "Sune Bergström is responsible for a crucial breakthrough in prostaglandin research."
• "The great breakthrough in prostaglandin research came in the late 1950s when Sune Bergström purified the first prostaglandins and determined their structure."