Definition of "tranquilizer" [tran•quil•i•zer]

• One that serves to tranquilize, as soothing music. (noun)
• Any of various drugs used to reduce tension or anxiety; an antianxiety agent. (noun)
• Any of various drugs used to treat psychotic states; an antipsychotic drug. Not in scientific use. (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.

• "So drugs like fluphenazine (a long-term tranquilizer) is not allowed under most racing jurisdictions or under USEF and FEI rules, but racing jurisdictions may not expend the cost at the lab level to detect this drug that USEF and FEI would because of the potential for abuse in jumpers and show horses."
• "Shooting the animal with a tranquilizer is an option, according to Graves."
• "And cases from one kind of tranquilizer nearly doubled."