tran·​quil·​ize ˈtraŋ-kwə-ˌlīz How to pronounce tranquilize (audio)
variants or less commonly tranquillize
tranquilized also tranquillized; tranquilizing also tranquillizing

transitive verb

: to make tranquil or calm : pacify
especially : to relieve of mental tension and anxiety by means of drugs

intransitive verb

: to become tranquil : relax sense 1
: to make one tranquil

Example Sentences

They tranquilized the bear with a dart so that it could be safely moved to a different area. at long last the crying baby was tranquilized by the steady rocking of her cradle
Recent Examples on the Web The bear had been sitting 50 feet up a pine tree as deputies waited below for bear trappers to come tranquilize it, a Palm Beach County Sheriff’s Office news release says, but the trappers didn’t arrive in time. Shira Moolten, Sun Sentinel, 20 June 2022 Many asked wildlife officials to do something for the moose, to tranquilize it and treat it. Mitchell Willetts, Anchorage Daily News, 13 May 2022 An arms-control agreement can also help tranquilize the clerical regime’s domestic troubles. Reuel Marc Gerecht, National Review, 31 Mar. 2022 Lions living in such refuges aren’t able to disperse naturally, so maintaining physically and genetically healthy populations requires that wildlife managers frequently tranquilize lions and swap them between reserves. Brian Handwerk, Smithsonian Magazine, 30 Mar. 2022 But recently, Big Bruin apparently returned to its older patterns, and wildlife officers were able to tranquilize it in a vacant wood lot, TWRA said. Zoe Christen Jones, CBS News, 28 Mar. 2022 Current plans are to tranquilize Hank and his brethren, tag them, and move them to a place with few people. Nr Editors, National Review, 3 Mar. 2022 Wildlife officers Dawson Swanson and Scott Murdoch were able to tranquilize the bull on private property in Pine Junction on Saturday evening, according to a press release from the Colorado Department of Parks and Wildlife. Michael Hollan, Fox News, 12 Oct. 2021 Over that time, wildlife officials confirmed numerous sightings of the bull elk and tried several times to tranquilize it, all efforts at freeing it from its rubber-and-steel yoke. Washington Post, 12 Oct. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tranquilize.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1623, in the meaning defined at transitive sense

Time Traveler
The first known use of tranquilize was in 1623

Dictionary Entries Near tranquilize

Cite this Entry

“Tranquilize.” Dictionary, Merriam-Webster, Accessed 27 Nov. 2022.

Kids Definition



variants also tranquillize
tranquilized also tranquillized; tranquilizing also tranquillizing
: to make or become tranquil or relaxed
especially : to ease the nervous tension and anxiety of usually by means of drugs

Medical Definition


transitive verb

variants or chiefly British tranquillize or tranquillise
tranquilized or chiefly British tranquilized or tranquilised; tranquilizing or chiefly British tranquilizing or tranquilising
: to make tranquil or calm
especially : to relieve of mental tension and anxiety by means of drugs
tranquilization noun
or chiefly British tranquillization or tranquillisation

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