Definition of "vasoconstrictor" []

• Something, such as a nerve or drug, that causes vasoconstriction. (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.

• "Its all about caffeine being a vasoconstrictor and everything starting to open up when the caffeine gets low."
• "Tobacco also acts as a vasoconstrictor, (constrictor of blood vessels), reducing blood flow to an area, and temporarily raising blood pressure."
• "The ingredient in the drops, tetrahydrozaline hydrochloride, is a vasoconstrictor, so it might reduce skin redness too."