anesthesia

American  

[an-uhs-thee-zhuh] / ˌæn əsˈθi ʒə /

Or anaesthesia

noun

1. Medicine/Medical. general or local insensibility, as to pain and other sensation, induced by certain interventions or drugs to permit the performance of surgery or other painful procedures.

2. Pathology. general loss of the senses of feeling, as pain, heat, cold, touch, and other less common varieties of sensation.

3. Psychiatry. absence of sensation due to psychological processes, as in conversion disorders.

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anesthesia British  

/ ˌænɪsˈθiːzɪə /

noun

1. the usual US spelling of anaesthesia

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anesthesia Scientific  

/ ăn′ĭs-thē′zhə /

1. Total or partial loss of sensation to touch or pain, caused by nerve injury or disease, or induced intentionally, especially by the administration of anesthetic drugs, to provide medical treatment. The first public use of ether to anesthetize a patient in Boston in 1846 initiated widespread acceptance of anesthetics in the Western world for surgical procedures and obstetrics. General anesthesia, administered as inhalation or intravenous agents, acts primarily on the brain, resulting in a temporary loss of consciousness. Regional or local anesthesia affects sensation in a specific anatomic area, and includes topical application of local anesthetics, blocking of peripheral nerves, spinal anesthesia, and epidural anesthesia, which is used commonly during childbirth.

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anesthesia Cultural  

1. Loss of sensation or consciousness. Anesthesia can be induced by an anesthetic, by acupuncture, or as the result of injury or disease.

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Etymology

Origin of anesthesia

1715–25; < New Latin < Greek anaisthēsía want of feeling. See an- ¹, esthesia

Compare meaning

How does anesthesia compare to similar and commonly confused words? Explore the most common comparisons:

• anesthesia vs. anesthetic

Explanation

Anesthesia is a loss of sensation in a body part — or your entire body — caused by the administration of medication. If you're undergoing surgery, you'll need anesthesia to ensure you don't feel any pain during the procedure. Anesthesia, pronounced "an-es-THEE-zhuh," comes from the Greek word anaisthetos, meaning "without sensation." There are two kinds of anesthesia: local anesthesia numbs just part of your body, like when a dentist numbs your mouth before filling a cavity. General anesthesia makes you unaware and free of all sensation, like when you are having your spleen removed. The medication that causes the lack of sensation is called an anesthetic and the person who administers an anesthetic is an anesthesiologist.

Example Sentences

Further progress could refine these tools to better assess consciousness in coma, advanced dementia, and anesthesia, and influence treatment decisions and end-of-life care.

From Science Daily • Feb. 1, 2026

"Successful surgery completed, without complications. Now we wait for him to wake up from anesthesia," his spouse, Michelle Bolsonaro, announced in an Instagram post.

From Barron's • Dec. 25, 2025

“We were very prepared to handle any lung problems the baby might have. But he came out of anesthesia pretty quickly and he was feisty,” Dayanim said.

From Los Angeles Times • Dec. 12, 2025

From there, Fleischacker’s doctor sent her to a nearby hospital to get the exam under general anesthesia.

From Salon • Jun. 9, 2025

He went under anesthesia for what he thought was a routine procedure and woke up permanently paralyzed from the waist down.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot