anesthesia

UK: /ˌænɪsˈθiːziə/ US: /ˌænəsˈθiʒə/ ,(an′əs thē′zhə)

WordReference Random House Learner's Dictionary of American English © 2026

an•es•the•sia or an•aes•the•sia /ˌænəsˈθiʒə/   n. [uncountable]

1. loss of sensation in the whole body or in certain areas:
   drugs that induce anesthesia in surgical patients.

WordReference Random House Unabridged Dictionary of American English © 2026

an•es•the•sia  (an′əs thē′zhə), n. 

1. Medicine 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.

Also, anaesthesia. 

• Greek anaisthēsía want of feeling. See an-¹, esthesia
• Neo-Latin
• 1715–25

Collins Concise English Dictionary © HarperCollins Publishers::

anesthesia / ˌænɪsˈθiːzɪə/ noun

1. the usual US spelling of anaesthesia

WordReference Random House Learner's Dictionary of American English © 2026

an•aes•the•sia /ˌænəsˈθiʒə/   n. 

1. Medicine, Pathology anesthesia.

an•aes•thet•ic /ˌænəsˈθɛtɪk/  n. [countable] , adj. 
an•aes•the•tist /əˈnɛsθɪtɪst/  n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2026

an•aes•the•sia  (an′əs thē′zhə), n. [Med., Pathol.]

1. Medicine, Pathology anesthesia.

an•aes•thet•ic  (an′əs thet′ik), adj., n.  an•aes•the•tist  (ə nes′thi tist or, esp. Brit., ə nēs′-), n. 

Collins Concise English Dictionary © HarperCollins Publishers::

anaesthesia, anesthesia / ˌænɪsˈθiːzɪə/ noun

1. local or general loss of bodily sensation, esp of touch, as the result of nerve damage or other abnormality
2. loss of sensation, esp of pain, induced by drugs: called general anaesthesia when consciousness is lost and local anaesthesia when only a specific area of the body is involved

Also called: anaesthesis Etymology: 19th Century: from New Latin, from Greek anaisthēsia absence of sensation, from an- + aisthēsis feeling