an·​es·​the·​sia | \ ˌa-nəs-ˈthē-zhə \

Definition of anesthesia

1 : loss of sensation with or without loss of consciousness The patient was given intravenous medication to induce anesthesia. … doctors freeze the tumor with little coils filled with liquid nitrogen that are inserted in the prostate under anesthesia.— Andy Grove Awareness during anesthesia is a serious complication with potential long-term psychological consequences.— Michael S. Avidan et al. We often radiograph dogs when they are under anesthesia for spaying or neutering or other routine procedures.— Bonnie Wilcox — see also general anesthesia, local anesthesia
2 : an agent that produces anesthesia : anesthetic A capnometer measures the amount of carbon dioxide in exhaled air, thereby insuring that the tubes bringing oxygen and anesthesia to the patient are properly placed.— Lisa Belkin She was still groggy from her anesthesia, and she had an I.V. tube in her arm.The New Yorker These substances [=endorphins], which have been identified in recent years through research on brain chemistry, act as a natural anesthesia that can lessen extreme pain.— Norman Cousins … the baby emerges while the woman is unconscious, under a general anesthesia such as ether or nitrous oxide.— Deborah Tanzer

Examples of anesthesia in a Sentence

The patient was given an injection to induce anesthesia.

Recent Examples on the Web

After that, the anesthesia should kick in, and your mole plus the surrounding area should be nice and numb. Korin Miller, SELF, "What You Can Expect Before, During, and After Mole Removal," 28 July 2018 The one- to three-hour procedure (larger breasts take longer) is typically done under local anesthesia or IV sedation, and is considered to be minimally invasive. Jolene Edgar, Harper's BAZAAR, "Everything You Need To Know About The Non-Surgical Breast Lift," 17 Aug. 2018 Medical aesthetics exist in the place between hardcore plastic surgery, with anesthesia and downtime, and a more superficial procedure like getting a blowout. Cheryl Wischhover, Vox, "The push to make Botox as common as getting a blowout," 12 Sep. 2018 The patient was administered anesthesia prior to the surgery. Michael Bartiromo, Fox News, "California mom claiming emergency C-section was administered without anesthesia given $25 gift card as apology, fiancé says," 6 Aug. 2018 Hospitals also are grappling with shortages of regional anesthesia — local injections of lidocaine, bupivacaine and a third painkiller standard for eye surgery, orthopedic procedures and knee and hip replacements. Washington Post, "US hospitals grapple with prolonged injected opioid shortage," 27 June 2018 Atrium says steps it's taken to ensure a smooth transition include conducting drills with the new doctors and Atrium's nurse anesthetists — specialists trained to administer anesthesia under the supervision of a physician. Deon Roberts, charlotteobserver, "Atrium nears big change with its anesthesiologists. Here's what patients should expect," 19 June 2018 Anthem’s Medical Policy and Technology Assessment Committee, a majority of whom are external physicians, reviewed the available evidence addressing the use of general anesthesia and monitored anesthesia care for cataract surgery. Michelle Andrews, sacbee, "Anthem calls on eye surgeons to monitor anesthesia during cataract surgery | The Sacramento Bee," 27 Feb. 2018 Previous iterations of this procedure relied on anesthesia to keep the oryx manageably calm. Katherine J. Wu, Smithsonian, "New Artificial Insemination Technique Successfully Breeds Critically Endangered Scimitar-Horned Oryx," 10 July 2018

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

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First Known Use of anesthesia

circa 1721, in the meaning defined at sense 1

History and Etymology for anesthesia

New Latin, from Greek anaisthēsia insensibility, from a- + aisthēsis perception, from aisthanesthai to perceive — more at audible

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Last Updated

14 Jan 2019

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Time Traveler for anesthesia

The first known use of anesthesia was circa 1721

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More Definitions for anesthesia



English Language Learners Definition of anesthesia

medical : loss of feeling in a person's body or part of the body through the use of drugs


an·​es·​the·​sia | \ ˌa-nəs-ˈthē-zhə \

Kids Definition of anesthesia

: loss of feeling in all or part of the body with or without loss of consciousness The patient was given an injection before surgery to produce anesthesia.


variants: or chiefly British anaesthesia \ ˌan-​əs-​ˈthē-​zhə \

Medical Definition of anesthesia

1 : loss of sensation especially to touch usually resulting from a lesion in the nervous system or from some other abnormality
2 : loss of sensation and usually of consciousness without loss of vital functions artificially produced by the administration of one or more agents that block the passage of pain impulses along nerve pathways to the brain

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Rhyming Dictionary: Words that rhyme with anesthesia

Spanish Central: Translation of anesthesia

Nglish: Translation of anesthesia for Spanish Speakers

Britannica English: Translation of anesthesia for Arabic Speakers Encyclopedia article about anesthesia

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