an·es·the·sia also an·aes·the·sia (ăn′ĭs-thēzhə)
1. Total or partial loss of sensation, especially tactile sensibility, induced by disease, injury, acupuncture, or an anesthetic, such as chloroform or nitrous oxide.
2. Local or general insensibility to pain with or without the loss of consciousness, induced by an anesthetic.
3. Medication that induces partial or total loss of sensation and may be topical, local, regional, or general, depending on the method of administration and area of the body affected.
[New Latin anaesthēsia, from Greek anaisthēsiā, insensibility : an-, without; see A-1 + aisthēsis, feeling (from aisthanesthai, aisthē-, to feel; see au- in the Appendix of Indo-European roots).]
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