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.
So, while they are rarely used to induce anesthesia, they are frequently used along with other agents such as intravenous non-opioid anesthetics or inhalational anesthetics. Furthermore, they are used to relieve pain of patients before, during, or after surgery.