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anesthesia vs. anesthetic

[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.

[an-uhs-thet-ik] / ˌæn əsˈθɛt ɪk /
Or anaesthetic

noun

  1. a substance that produces anesthesia, as halothane, procaine, or ether.

adjective

  1. pertaining to or causing physical insensibility.

    an anesthetic gas.

  2. physically insensitive.

    Halothane is used to produce an anesthetic state.