adjective, sourer, sourest. 1. having an acid taste, resembling that of vinegar, lemon juice, etc.; tart. 2. rendered acid or affected by fermentation; fermented. 3. producing the one of the four basic taste sensations that is not bitter, salt, or sweet. 4. characteristic of something fermented: a sour smell.
General anesthetics normally are used to produce loss of consciousness before and during surgery. However, for obstetrics (labor and delivery) or certain minor procedures, an anesthetic may be given in small amounts to relieve anxiety or pain without causing unconsciousness.
The earliest examples of general anesthesia include ether and chloroform. But, there is a fine line between the amount of these drugs needed for surgery and the amount that can be fatal; these drugs were often administered with nothing more than a soaked sponge to the nose, which made it hard to control the dose.